F5SN(H)Xe+; a rare example of xenon bonded to sp 3-hybridized nitrogen; synthesis and structural characterization of [F5SN(H)Xe][AsF6]

Article abstract of DOI:10.1021/ic702039f

The salt [F₅SN(H)Xe][AsF₆] has been synthesized by the reaction of [F₅SNH₃][AsF₆] with XeF ₂ in anhydrous HF (aHF) and BrF₅ solvents and by solvolysis of [F₃S=NXeF][AsF₆] in aHF. Both F ₅SN(H)Xe⁺ and F₅SNH₃⁺ have been characterized by ¹²⁹Xe, ¹⁹F, and ¹H NMR spectroscopy in aHF (-20°C) and BrF₅ (supercooled to -70°C). The yellow [F₅SN(H)Xe][AsF₆] salt was crystallized from aHF at -20°C and characterized by Raman spectroscopy at -45°C and by single-crystal X-ray diffraction at -173°C. The Xe-N bond length (2.069(4) A) of the F₅SN(H)Xe⁺ cation is among the shortest Xe-N bonds presently known. The cation interacts with the AsF₆^- anion by means of a Xe...F-As bridge in which the Xe...F distance (2.634(3) A) is significantly less than the sum of the Xe and F van der Waals radii (3.63 A) and the AsF₆ ^- anion is significantly distorted from O_h symmetry. The ¹⁹F and ¹²⁹Xe NMR spectra established that the [F ₅SN(H)Xe][AsF₆] ion pair is dissociated in aHF and BrF₅ solvents. The F₅SN(H)Xe⁺ cation decomposes by HF solvolysis to F₅SNH₃⁺ and XeF ₂, followed by solvolysis of F₅SNH₃⁺ to SF₆ and NH₄⁺. A minor decomposition channel leads to small quantities of F₅SNF₂. The colorless salt, [F₅SNH₃][AsF₆], was synthesized by the HF solvolysis of F₃S≡NAsF₅ and was crystallized from aHF at -35°C. The salt was characterized by Raman spectroscopy at -160°C, and its unit cell parameters were determined by low-temperature X-ray diffraction. Electronic structure calculations using MP2 and DFT methods were used to calculate the gas-phase geometries, charges, bond orders, and valencies as well as the vibrational frequencies of F₅SNH ₃⁺ and F₅SN(H)Xe⁺ and to aid in the assignment of their experimental vibrational frequencies. In addition to F ₅TeN(H)Xe⁺, the F₅SN(H)Xe⁺ cation provides the only other example of xenon bonded to an sp³-hybridized nitrogen center that has been synthesized and structurally characterized. These cations represent the strongest Xe-N bonds that are presently known.

Full text of DOI:10.1021/ic702039f

Inorg. Chem. 2008, 47, 4173-4184
+
3
F SN(H)Xe ; a Rare Example of Xenon Bonded to sp -Hybridized
5
Nitrogen; Synthesis and Structural Characterization of [F SN(H)Xe][AsF ]
5
6
Gregory L. Smith, Hélène P. A. Mercier, and Gary J. Schrobilgen*
Contribution from the Department of Chemistry, McMaster UniVersity,
Hamilton, Ontario L8S 4M1, Canada
Received October 14, 2007
The salt [F
aHF) and BrF
been characterized by 129Xe, F, and H NMR spectroscopy in aHF (-20 °C) and BrF
5
SN(H)Xe][AsF
6
] has been synthesized by the reaction of [F
5
SNH
3
][AsF
6
] with XeF
2
in anhydrous HF
3+
+
(
5
solvents and by solvolysis of [F
3 6
St NXeF][AsF ] in aHF. Both F
5
SN(H)Xe and F
5
SNH have
19
1
5
(supercooled to -70 °C).
The yellow [F
5
SN(H)Xe][AsF
6
] salt was crystallized from aHF at -20 °C and characterized by Raman spectroscopy
+
at -45 °C and by single-crystal X-ray diffraction at -173 °C. The Xe-N bond length (2.069(4) Å) of the F
cation is among the shortest Xe-N bonds presently known. The cation interacts with the AsF
5
SN(H)Xe
-
6
anion by means
of a Xe---F-As bridge in which the Xe---F distance (2.634(3) Å) is significantly less than the sum of the Xe and
-
19
129
F van der Waals radii (3.63 Å) and the AsF
NMR spectra established that the [F SN(H)Xe][AsF
cation decomposes by HF solvolysis to F
A minor decomposition channel leads to small quantities of F
synthesized by the HF solvolysis of F St NAsF and was crystallized from aHF at -35 °C. The salt was characterized
6
anion is significantly distorted from O
h
symmetry. The F and Xe
+
5
6
] ion pair is dissociated in aHF and BrF
5
5
solvents. The F SN(H)Xe
5
SNH and XeF
3+
2
, followed by solvolysis of F
5
SNH to SF
3+
6
and NH
4+
.
5 2
SNF . The colorless salt, [F
5
3
SNH ][AsF ], was
6
3
5
by Raman spectroscopy at -160 °C, and its unit cell parameters were determined by low-temperature X-ray
diffraction. Electronic structure calculations using MP2 and DFT methods were used to calculate the gas-phase
3+
+
geometries, charges, bond orders, and valencies as well as the vibrational frequencies of F
and to aid in the assignment of their experimental vibrational frequencies. In addition to F
5
SNH and F SN(H)Xe
5
+
+
5
TeN(H)Xe , the F SN(H)Xe
5
3
cation provides the only other example of xenon bonded to an sp -hybridized nitrogen center that has been synthesized
and structurally characterized. These cations represent the strongest Xe-N bonds that are presently known.
7
7,9
10
Introduction
zenenitrile, perfluoroalkylnitriles,
perfluoropyridines,
9
and s-trifluorotriazine. Until the present work, the only
example of a noble gas bonded to a formally sp -hybridized
nitrogen atom was [F
reported from this laboratory. The F
represents the most covalent Xe-N bonded species reported
to date and was synthesized by reaction of the XeF cation
Until recently, the only known Xe-N bonded compounds
were those containing sp - or sp-hybridized nitrogen
centers, namely, FXeN(SO
3
2
TeN(H)Xe][AsF
6
], which was recently
TeN(H)Xe cation
1
–3
2,4
5
2
F)
2
+
,
Xe[N(SO
2 2 2
F) ] ,
1
1
+
5
+
2,4,5
5
6
F[XeN(SO
2
F)
2
]
2
,
XeN(SO
2
F)
2
, Xe[N(SO CF ) ] , and
2
3 2 2
+
7,8
7
the XeF adducts of HCN, alkylnitriles, pentafluoroben-
+
*
Author to whom correspondence should be addressed. E-mail:
with F
5
TeNH
2
in anhydrous HF (aHF), and by reaction of
in aHF and BrF solvents. Most
schrobil@mcmaster.ca.
1) LeBlond, R. D.; DesMarteau, D. D. J. Chem. Soc., Chem. Commun.
+
F
5
TeNH
3
and XeF
2
5
(
(
(
(
(
(
1
974, 555–556.
recently, the synthesis and structural characterization of the
2) DesMarteau, D. D.; LeBlond, R. D.; Hossain, S. F.; Nothe, D. J. Am.
Chem. Soc. 1981, 103, 7734–7739.
(7) Emara, A. A. A.; Schrobilgen, G. J. J. Chem. Soc., Chem. Commun.
1987, 1644–1646.
3) Sawyer, J. F.; Schrobilgen, G. J.; Sutherland, S. J. Inorg. Chem. 1982,
2
1, 4064–4072.
(8) Emara, A. A. A.; Schrobilgen, G. J. Inorg. Chem. 1992, 31, 1323–
1332.
4) Schumacher, G. A.; Schrobilgen, G. J. Inorg. Chem. 1983, 22, 2178–
2
183.
(9) Schrobilgen, G. J. J. Chem. Soc., Chem. Commun. 1988, 1506–1508.
(10) Emara, A. A. A.; Schrobilgen, G. J. J. Chem. Soc., Chem. Commun.
1988, 257–259.
5) Faggiani, R.; Kennepohl, D. K.; Lock, C. J. L.; Schrobilgen, G. J.
Inorg. Chem. 1986, 25, 563–571.
6) Foropoulos, J. J.; DesMarteau, D. D. J. Am. Chem. Soc. 1982, 104,
(11) Fir, B. A.; Whalen, J. M.; Mercier, H. P. A.; Dixon, D. A.; Schrobilgen,
G. J. Inorg. Chem. 2006, 45, 1978–1996.
4
260–4261.
1
0.1021/ic702039f CCC: $40.75  2008 American Chemical Society
Inorganic Chemistry, Vol. 47, No. 10, 2008 4173
Published on Web 04/12/2008

Smith et al.
+
F
3
St NXeF cation, a rare example of a noble-gas compound
°C and supercooled to -70 °C, respectively). In both
+
+
in which the noble-gas atom is bonded to an inorganic sp-
hybridized nitrogen center, was reported by the authors.
In the latter study, the previously demonstrated Lewis
synthetic approaches, F
observed in equilibrium with XeF
best described as a solvent- and temperature-dependent
equilibrium. In BrF and aHF solutions below -20 °C,
5
SNH
3
and F
5
SN(H)Xe were
1
2
2
and HF, so that eq 3 is
1
3
basicity of thiazyl trifluoride, Nt SF
3
,
was exploited by
5
+
14
-
reaction of the Lewis acidic XeF cation, a2s its AsF
6
salt,
equilibrium 3 lies to the right, while in aHF above -20 °C,
1
+
with Nt SF
3
to form [F
3
St NXeF][AsF
6
].
no F
5
SN(H)Xe is observed.
In view of the solvolytic behavior of Nt SF
3
in aHF, which
-
20 ° C
1
5
16
gives rise to F
superacidic medium AsF
which forms the room-temperature stable Lewis acid–base
5
SNH
2
and to [F
5 3
SNH ][AsF
6
]
in the
[F St NXeF][AsF ] + HF
8 [F SN(H)Xe][AsF ] (2)
3
6
5 6
HF
5
/aHF, and the basicity of F
5 2
SNH ,
HF or
1
7
[F SNH ][AsF ] + XeF yBrF5z
adducts, F
5
SNH
2
·BF
3
and F
5
SNH
2
5
·PF ,
two synthetic
5
3
6
2
+
5
approaches to the formation of the F SN(H)Xe cation were
[
F SN(H)Xe][AsF ] + 2HF (3)
5
6
developed that are described in the present paper: (1) the
reaction of [F SNH ][AsF ] with XeF in aHF and BrF
solvents and (2) the HF solvolysis of [F St NXeF][AsF ],
5
3
6
2
5
(
c) Decompositions of [F
5
SNH
3
][AsF
6
] and [F
5
SN(H)-
][AsF
3
6
Xe][AsF
6
] in aHF. The decompositions of [F
5
SNH
3
6
]
providing avenues to the second example of xenon bound
and [F SN(H)Xe][AsF
5
6
] in aHF at 0 °C were monitored by
3
to a formally sp -hybridized nitrogen center.
19
+
F NMR spectroscopy. The F
solvolysis in aHF to form F
5
SN(H)Xe cation underwent
+
19
5
SNH
3
2
and XeF [δ( F) )
Results and Discussion
1
19
129
-
194.5 (-185.0) ppm, J( F- Xe) ) 5652 (5611) Hz]
+
according to the reverse of eq 3. The F
underwent further solvolysis (eq 4) to form SF
54.1 (56.0) ppm, J( F- S) ) 251.9 Hz] and NH
) 5.54 ppm, J( H- N) ) 51 Hz]. Small amounts of
5
SNH
3
cation
Syntheses of [F
5 3 6
SNH ][AsF ] and [F
5
SN(H)Xe][AsF
6
].
and
1
9
+
6
[δ( F) )
The solvolytic reactions leading to the F
5
SNH
3
1
19
33
+
1
+
4
[δ( H)
F
5
SN(H)Xe cations and their further solvolyses were
1
1
14
1
19
129
monitored by H, F, and Xe NMR spectroscopy in both
aHF and BrF solvents. The NMR parameters reported in
this section (parameters obtained in BrF are given in
+
F
5
SNF
2
also formed in the course of F
5
SN(H)Xe decom-
5
+
+
position. The [F
5
SNH
3
]/[F
5
SN(H)Xe ]/[F
5
SNF
2
]/[SF
6
]
5
5
molar ratios at -20 °C in BrF and aHF were 1.00:0.17:
.02:0.47 and 1.00:0.01:0.01:0.44, respectively.
parentheses) are for previously known species and are not
further discussed. Those of the title species are discussed in
the NMR Spectroscopy section that follows.
0
-20 to 0 ° C
[
F SNH ][AsF ] + HF
8 SF + [NH ][AsF ] (4)
5
3
6
6 4 6
(
a) [F
St NAsF
reaction of Nt SF
5
SNH
3
][AsF
6
]. The donor-acceptor adduct,
HF
1
8
F
3
5
, was prepared as previously described, by
The formation of F
reactions (eqs 5-10) analogous to those leading to F
also a minor product in the decomposition of the F
5
5
SNF
2
likely results from a series of
TeNF
TeN-
SN(H)Xe to form
2
SNF is consistent with the nucleophilic fluorination of
3
with AsF
5
at -78 °C for ca. 1 h, forming
SNH ][AsF ],
was synthesized as previously described by reaction of
St NAsF
5
2
,
a friable white solid. The ammonium salt, [F
5
3
6
1
6
+
11
+
(
H)Xe cation. The decomposition of F
5
F
3
5
with aHF at 0 °C for ca. 6 h (eq 1), forming
F
F
5
colorless, featherlike crystals. In both instances, the products
+
5
SN(H)Xe accompanied by the liberation of xenon gas
and formation of the nitrenium ion, F
ate (eq 5). Nucleophilic attack by the F ion leads to the
5
known fluoramine, F SNHF, according to eq 6.
were characterized by Raman spectroscopy at -160 °C.
+
5
SNF , as an intermedi-
0
° C
-
F St NAsF + 3HF
8 [F SNH ][AsF ]
(1)
3
5
5
3
6
19
HF
The enhanced fluoroacidity that results from fluorination
of the nitrenium cation (eq 6) also results in the formation
(
b) [F
5
SN(H)Xe][AsF
6
]. The solvolysis of [F
in aHF over a period of ca. 4 h at -20 °C led to
] formation according to eq 2. The salt
3
St NXeF]
1
2
[
[
6
AsF ]
+
+
of the strong oxidant cations, XeF and Xe
2
F
3
(eqs 7 and
SNHF to
cation is expected to
, which is
F
5
SN(H)Xe][AsF
6
8
F
), which may be expected to fluorinate F
5
was obtained as transparent yellow plates and was character-
+
+
+
5
SNHF
2
5 2
(eq 9). The F SNHF
ized by Raman spectroscopy at -45 °C. The F
cation was also formed by reaction of [F SNH ][AsF
XeF in aHF and BrF solvents (eq 3) at -30 °C for ca. 30
min and was characterized by F NMR spectroscopy (at -20
5
SN(H)Xe
readily deprotonate (eq 10) by analogy with NF
too weakly basic to be protonated in the AsF /HF solution.
The NMR parameters determined for F SNF in HF at -20
C in this work [δ( Feq) ) 31.5 ppm (doublet of triplets),
3
5
3
6
] with
20
5
2
5
19
5
2
1
9
°
1
9
2
19
19
(
(
(
12) Smith, G. L.; Mercier, H. P. A.; Schrobilgen, G. J. Inorg. Chem. 2007,
6, 1369–1378.
13) Glemser, O.; Mews, R. Angew. Chem., Int. Ed. Engl. 1980, 19, 883–
δ( F ) ) 66.3 ppm (quintet), J( Fax- Feq) ) 157.1 Hz
and J( F - Feq) ) 13.8 Hz] are in good agreement with
the previously reported parameters [δ( Fax) ) 48.5 ppm
21
N
4
3
19
19
N
1
9
8
99.
2
1
19
14) Schrobilgen, G. J. In Synthetic Fluorine Chemistry; Olah, G. A.,
Chambers, R. D., Prakash, G. K. S., Eds.; John Wiley & Sons: New
York, 1992; pp 1–30.
(
quintet), δ( Feq) ) 36.5 ppm (doublet of triplets),
(
(
15) Clifford, A. F.; Duncan, L. C. Inorg. Chem. 1966, 5, 692–693.
(19) DesMarteau, D. D.; Eysel, H. H.; Oberhammer, H.; Günther, H. Inorg.
Chem. 1982, 21, 1607–1616.
16) Meier, T.; Hoppenheit, R.; Mews, R. Z. Anorg. Allg. Chem. 1993,
6
19, 1241–1246.
(20) Christe, K. O. Inorg. Chem. 1975, 14, 2821–2824.
(21) Stump, E. C., Jr.; Padgett, C. D.; Brey, W. S., Jr. Inorg. Chem. 1963,
2, 648–649.
(
(
17) Clifford, A. F.; Zeilenga, G. R. Inorg. Chem. 1969, 8, 1789–1791.
18) Glemser, O.; Koch, W. An. Asoc. Quim. Argent. 1971, 59, 143–148.
4174 Inorganic Chemistry, Vol. 47, No. 10, 2008

F
5
SN(H)Xe+
a
Table 1. NMR Chemical Shifts and Spin-Spin Coupling Constants for [F5SNH3][AsF6] and [F5SN(H)Xe][AsF6]
species
chemical shifts, ppm
coupling constants, Hz
δ(129Xe)
δ( F)
19
δ( H)
1
2
J( Fax- Feq)
19
19
F5SNH3+
50.1 (50.0), Fax
8.92 (7.74)
152.6 (154.7)
7
1.7 (73.8), Feq
59.0 (59.6), Fax
1.3 (73.0), Feq
F5SN(H)Xe+
-2897 (-2956)
(9.57)
152.9 (154.7)
7
-
b
AsF6
SF6
-69 (-64)
54.1 (56.0)
c
+
d
NH4
XeF2
HF
5.54
e
-194.5 (-185.0)
-197 (-192)
(134.5), Feq
8.26 (7.39)
BrF5
(76.3)
(
272.0), Fax
a
The values in parentheses were measured in supercooled BrF5 solvent at -70 °C; all other values were measured in aHF solvent at -20 °C. The axial
and equatorial fluorines are denoted by Fax and Feq, respectively. The secondary isotope shifts arising from
3
4/32
19
S were measured in the F NMR spectra of
F5SNH3 and F5SN(H)Xe+ in aHF solvent: ∆ Fax(
+
1
19
34/32
S) ) -0.058 and -0.060 ppm, and ∆ Feq(
1
19
34/32
S) ) -0.056 and -0.056 ppm, respectively. The
b
1
9
-
F resonance of the AsF6 anion was broad and saddle-shaped in aHF [∆ν½ ) 2860 (700) Hz] as a result of partial quadrupolar collapse of the 1:1:1:1
1
75
19
c
34/32
19
1
19
34/32
1
19
33
quartet arising from J( As- F). The secondary isotope effects of
S on F, ∆ Fax(
in aHF solvent at -20 °C. J( H- N) ) 51 Hz. J( F- Xe) ) 5652 (5611) Hz.
21 22
S) ) -0.052 ppm, and J( F- S) ) 251.9 Hz were observed
d
1
1
14
e
1
19
129
19
2
19
19
δ( F ) ) 66.3 ppm (quintet), J( Fax- Feq) ) 153.2 Hz,
N
3
19
19
21
and J( F - Feq) ) 19 Hz ]. In the present study, the axial
N
fluorine resonance was obscured by overlap with the axial
+
fluorine resonance of F
5
SNH
3
(49.9 ppm, aHF, -20 °C).
3
19
19
The J( F
and prior studies, in accordance with the general inability to
resolve three-bond couplings to the axial fluorine of the F Te
N
- Fax) coupling was not resolved in the present
5
23
3
19
19
moiety. Similarly, the J( F
N
- Fax) coupling also was not
1
1
5 2
resolved in F TeNF .
+
+
F SN(H)Xe f [F SNH ] + Xe
(5)
5
5
+
-
+
[
F SNH ] + 2HF/AsF f F SNHF + H F /AsF (6)
5 6 5 2 5
AsF + XeF h [XeF][AsF ]
(7)
(8)
5
2
6
[
XeF][AsF ] + XeF h [Xe F ][AsF ]
6 2 2 3 6
+
+
3
F SNHF + XeF (Xe F ) f
5
2
1
9
+
F
i
g
u
r
e
1
.
T
h
e
F
N
M
R
s
p
e
c
t
r
u
m
(
4
7
0
.
5
9
2
M
H
z
)
o
f
F
5
S
N
(
H
)
X
e
i
n
+
2
HF solvent at –20 °C. Symbols denote the secondary isotope shifts,
F SNHF + Xe (Xe + XeF ) (9)
5
2
1
19 34/32
+
∆
F(
S), on Feq and Fax (†), and Feq of F5SNH3 (*).
+
F SNHF + HF f F SNF + H F
(10)
NMR Spectroscopy. The 1H, 19F, and 129Xe NMR
parameters for [F SNH ][AsF ] and [F SN(H)Xe][AsF ],
recorded in aHF solvent at -20 °C or BrF supercooled to
70 °C, are listed in Table 1 (NMR parameters obtained in
BrF are given in parentheses). The chemical shifts and
coupling constants are in accord with those of other F
5
2
5
2
2
This chemical shift is in agreement with that reported in
1
6
liquid SO
2
: 8.8 ppm (-40 °C). The line broadening and
5
3
6
5
6
absence of resolved couplings results from quadrupolar
relaxation by the directly bonded N atom (I ) 1).
(b) [F SN(H)Xe][AsF ]. The NMR spectra are consistent
with eqs 2 and 3 in which resonances arising from F SNH ,
5 3
6 4
SF , and NH (vide supra) (eqs 3 and 4) were also observed.
5
1
4
-
5
5
6
+
5
S
1
6,24
+
11
+
11
+
derivatives,
F
5
TeNH
][AsF
]. The 19F NMR spectrum of the
cation (Figure S1) is an AX spin-coupling pattern,
3
,
and F
5
TeN(H)Xe .
1
9
+
The F NMR spectrum of F SN(H)Xe (Figure 1)
5
(
a) [F
SNH
5
+
SNH
3
6
4
consists of an AB spin-coupling pattern at 71.3 (73.0)
F
5
3
4
[
doublet, Feq] and 59.0 (59.6) [quintet, Fax] ppm, with
occurring at 71.7 (73.8) [doublet, Feq] and 50.1 (50.0)
2
19
19
2
19
19
J( F - F ) ) 152.9 (154.7) Hz, that arises from the
[
quintet, Fax] ppm with J( Fax- Feq) ) 152.6 (154.7) Hz,
ax
eq
pseudo-octahedral F
similar to those of F
equatorial fluorine chemical shift, which is significantly
more deshielded in the xenon cation, a trend that was also
observed for the F TeN(H)Xe and F TeNH
3
logues. The additional fine structure observed on the
quintet results from second-order transitions, which were
confirmed by spectral simulation.
5
SN group. These parameters are very
that arises from the pseudo-octahedral F SN group. These
5
+
SNH
3
(vide supra), except for the
parameters are in good agreement with those previously
5
+
reported for F
5
SNH
3
2
in liquid SO : 76.37 and 52.43 ppm
1
6
and 156.5 Hz (-40 °C), respectively.
The H NMR spectrum of [F
+
+
1
ana-
5 3 6
SNH ][AsF ] consists of a
5
5
1
1
broad singlet at 8.92 (7.74) ppm [∆ν
½
) 23.0 (54.2) Hz].
(
(
(
22) Cady, G. H.; Eggers, D. F.; Tittle, B. Proc. Chem. Soc. 1963, 65–66.
23) See ref 11 and references therein.
129
+
The Xe NMR spectrum of F
5
SN(H)Xe is a singlet [∆ν
½
24) Merrill, C. I.; Williamson, S. M.; Cady, G. H.; Eggers, D. F., Jr. Inorg.
Chem. 1962, 1, 215–219.
1
29
) 128 (150) Hz] at -2897 (-2956) ppm. The high Xe
Inorganic Chemistry, Vol. 47, No. 10, 2008 4175

Smith et al.
shielding places the Xe-N bond among the most covalent
Table 2. Summary of Crystal Data and Refinement Results for
[F5SN(H)Xe][AsF6]
2
5
of Xe–N bonds, but it is considerably less shielded than
1
29
+
26
[F5SN(H)Xe][AsF6]
Xe in C
6 5
F
Xe (–3831 ppm, HF solvent, –40 °C). The
empirical formula
space group (No.)
a (Å)
b (Å)
c (Å)
HAsF11NSXe
P1 (2)
1
29
+
Xe shielding is very similar to that in F
5
TeN(H)Xe
j
(
–
–2841 ppm, HF solvent, –45 °C; –2902 ppm, BrF
5
solvent,
SN(H)Xe are
5.3248(9)
7.100(1)
11.877(2)
87.551(5)
83.398(5)
86.278(6)
444.8(1)
2
+
+
48 °C), and both F
5
TeN(H)Xe and F
5
1
29
considerably more shielded than the Xe resonances of
XeN(SO
F
R (deg)
ꢀ (deg)
γ (deg)
+
5
2
F)
2
(–1943 ppm, SbF
5
solvent, 25 °C),
+
3
St NXeF (–1652 ppm, HF solvent, –20 °C; –1661 ppm,
3
V (Å )
1
2
+
BrF
SbF
5 °C). As in the case of F
5
solvent, –60 °C), isovalent F
5
TeOXe (–1472 ppm,
molecules/unit cell
2
7
+
-
1
5
solvent, 5 °C), and XeF (–574 ppm, SbF solvent,
5
mol wt (g mol
)
462.275
3.452
2
8
+
11
129
Dcalcd (g cm-3)
2
5
TeN(H)Xe , the
Xe
T (°C)
-173
shielding may be used as a gauge of L-group electronega-
tivity and Xe–E bond covalency (L is an electronegative
ligand and E is a second row ligand atom), and the shielding
increases (group electronegativity decreases) with Xe–E bond
µ (mm-1)
7.95
wavelength (Å)
final agreement factors
0.71073
R1 ) 0.0218
wR2 ) 0.0481
a
a
R1 is defined as ∑|Fo| - |Fc|/∑|Fo| for I > 2σ(I); wR2 is defined as
+
covalency for the series of LXe cations, that is, Xe–C >
2
2 2
2 2 1/2
[
∑[w(Fo - Fc ) ]/∑w(Fo ) ] for I > 2σ(I).
1
29
14
Xe–N > Xe–O > Xe–F. The Xe– N coupling is not
+
observed in F
5
SN(H)Xe because of quadrupolar relaxation
In [F
Xe---F(6) (2.634(4) Å) bond lengths are somewhat longer
than their counterparts in [F TeN(H)Xe][AsF ] (2.044(4) and
.580(3), respectively), while the Xe–N–H, N–Xe---F(6), and
5 6
SN(H)Xe][AsF ], the Xe–N (2.069(4) Å) and
1
4
of N resulting from the low symmetry (high electric field
gradient) at the nitrogen nucleus. The broad Xe line widths
129
5
6
+
of F
5
SN(H)Xe recorded at 11.7440 T precluded observation
2
2
129
1
of the long-range couplings to xenon, namely, J( Xe– H),
S/Te–N–Xe angles are all equal within experimental error,
and the As–F(6) bond lengths (1.759(4) Å and 1.740(4) Å,
respectively) are similar. The longer Xe–N and Xe---F(6)
bond lengths in the sulfur analogue are offset by the expected
shorter S–N (1.761(4) Å), S–Fax (1.559(3) Å), and average
S–Feq (1.573(4) Å) bond lengths when compared with the
Te–N (1.982(5) Å), Te–Fax (1.791(4) Å), and average Te–Feq
3
129
19
3
129
19
J( Xe– Fax), and J( Xe– Feq), which are presumably,
1
29
in large measure, attributable to the relaxation of Xe by
shielding anisotropy (SA), and also were not observed for
+
11
F
5
TeN(H)Xe .
1
SN(H)Xe+ consisted of a
supercooled to –70 °C, but the
coupling to N was not observed, as a result of quadrupolar
The H NMR spectrum of F
5
singlet at 9.57 ppm in BrF
5
1
4
5 6
(1.811(5) Å) bond lengths of [F TeN(H)Xe][AsF ] and
2
129
1
relaxation. Failure to observe the J( Xe– H) coupling is
account for the smaller unit cell volume of the sulfur
analogue.
The contributions to the total bond valency of xenon in
129
also attributed to broadening of the Xe satellites as a result
of a significant SA contribution to T at the high external
field strength used to obtain the H NMR spectra.
X-ray Crystal Structure of [F SN(H)Xe][AsF
1
1
5 6 5 6
[F SN(H)Xe][AsF ] and [F TeN(H)Xe][AsF ] have been
5
6
]. A
determined for the Xe–N bond, the Xe---F contact to the
summary of the refinement results and other crystallographic
information are provided in Table 2. Important bond lengths
–
AsF
6
anion of the ion pair, and all long Xe---F contacts
that fall within the sum of the xenon and fluorine van der
and angles for [F
with calculated values for the F
cations. The [F SN(H)Xe][AsF ] unit cell is isomorphous
with that of [F TeN(H)Xe][AsF
5
SN(H)Xe][AsF
6
] are listed in Table 3 along
29
Waals radii (3.63 Å) according to the method described
+
+
5
SN(H)Xe and F
5
SNH
3
30
5
by Brown (Table S1). The xenon atom in [F SN(H)Xe]-
5
6
[
AsF
Xe---F(6B), 3.387 Å; Xe---F(5A), 3.271 Å; Xe---F(2A),
.267 Å; Xe---F(1A), 3.376 Å; and Xe---F(1B), 3.225 Å],
6
] has six long Xe---F contacts [Xe---F(6A), 3.342 Å;
1
1
j
and belongs to the P1
5
6
]
space group. The sulfur analogue has a unit cell volume that
3
3
is 27.6(6) Å smaller than that of the tellurium analogue.
compared to four Xe---F contacts in the tellurium salt which,
in the latter case, are somewhat shorter in order to achieve
a similar total bond valency at Xe. The longer Xe–N and
Xe---F bridge bonds of the sulfur analogue have a bond
valency sum at Xe (1.020 v.u.) that is 0.088 bond valence
units less than that of the tellurium analogue (1.108 v.u.).
The six long Xe---F contacts in the sulfur salt, however, have
a bond valency sum that is 0.038 bond valency units greater
than the sum for the four long Xe---F contacts of the
tellurium analogue 0.148 v.u. The two additional long
+
–
The F
5 6
SN(H)Xe cation and the AsF anion form an ion
pair by interaction through a Xe---F–As fluorine bridge
–
(
6 h
Figure 2a) in which the AsF anion is distorted from O to
approximate C4V local symmetry. The symmetry lowering
experienced by the anion is shown in the crystal structure to
be very close to an axial distortion in which the four
equatorial As–F bonds are equal to within (3σ and the As–F
bond trans to the elongated bridging As---F bond is equal to
the equatorial As–F bonds within (3σ, thus preserving the
4
-fold principal axis.
5 6
contacts in [F SN(H)Xe][AsF ] partly compensate for the
(
(
(
25) Gerken, M.; Schrobilgen, G. J. Coord. Chem. ReV. 2000, 197, 335–
(28) Schrobilgen, G. J.; Holloway, J. H.; Granger, P.; Brevard, C. Inorg.
Chem. 1978, 17, 980–987.
3
95.
26) Koppe, K.; Bilir, V.; Frohn, H. J.; Mercier, H. P. A.; Schrobilgen,
G. J. Inorg. Chem. 2007, 46, 9425–9437.
(29) Bondi, A. J. Phys. Chem. 1964, 68, 441–451.
(30) Brown, I. D. The Chemical Bond in Inorganic Chemistry; Oxford
University Press: Oxford, U.K., 2002.
27) Keller, N.; Schrobilgen, G. J. Inorg. Chem. 1981, 20, 2118–2129.
4176 Inorganic Chemistry, Vol. 47, No. 10, 2008

F
5
SN(H)Xe+
Table 3. Experimental Geometry for [F5SN(H)Xe][AsF6] and Calculated Geometries for F5SN(H)Xe+ and F5SNH3+a
Bond Lengths (Å)
F5SN(H)Xe+ (C1)
F5SNH3+ (C1)
b
c
exptl
calcd
calcd
MP2
SVWN
MP2
SVWN
Xe(1)-N(1)
N(1)-S(1)
N(1)-H(1)
N(1)-H(2)
N(1)-H(3)
S(1)-F(1)
S(1)-F(2)
S(1)-F(3)
S(1)-F(4)
S(1)-F(5)
Xe(1)---F(6)
2.069(4)
1.761(4)
0.801
2.065
1.822
1.028
2.095
1.805
1.042
1.853
1.023
1.023
1.022
1.531
1.567
1.567
1.567
1.567
1.853
1.045
1.044
1.044
1.561
1.595
1.594
1.594
1.594
d
1.559(3)
1.565(3)
1.578(3)
1.578(3)
1.571(3)
2.634(3)
1.544
1.578
1.578
1.591
1.561
1.548
1.589
1.583
1.596
1.569
2.251
Bond Angles (deg)
F5SN(H)Xe+ (C1)
F5SNH3+ (C1)
b
c
exptl
calcd
calcd
MP2
SVWN
MP2
SVWN
Xe(1)-N(1)-S(1)
Xe(1)-N(1)-H(1)
S(1)-N(1)-H(1)
S(1)-N(1)-H(2)
S(1)-N(1)-H(3)
N(1)-S(1)-F(1)
N(1)-S(1)-F(2)
N(1)–S(1)–F(3)
N(1)–S(1)–F(4)
N(1)–S(1)–F(5)
F(1)–S(1)–F(2)
F(1)–S(1)–F(3)
F(1)–S(1)–F(4)
F(1)–S(1)–F(5)
F(2)–S(1)–F(3)
F(2)–S(1)–F(4)
F(2)–S(1)–F(5)
F(3)–S(1)–F(4)
F(3)–S(1)–F(5)
F(4)–S(1)–F(5)
115.3(2)
115.0
101.2
104.9
113.5
101.1
104.5
d
107.2
106.9
d
110.0
109.2
109.4
179.2
87.9
86.2
87.2
87.0
92.9
92.9
92.9
92.9
174.1
89.7
89.7
90.0
90.0
174.1
109.0
108.8
108.7
179.2
88.0
86.5
87.0
87.4
92.8
92.8
92.8
92.8
174.4
89.8
89.7
90.0
89.9
174.4
176.7(2)
87.4(2)
94.0(2)
88.5(2)
90.7(2)
89.6(2)
89.0(2)
90.2(2)
90.5(2)
178.4(2)
89.2(2)
90.5(2)
90.0(2)
90.2(2)
179.2(2)
177.4
86.1
89.8
91.6
86.4
92.1
91.9
90.3
91.6
175.9
89.8
90.1
89.6
90.2
178.0
176.6
85.7
90.3
92.2
85.9
92.0
92.1
90.4
91.6
175.9
89.9
89.9
89.8
90.3
178.1
a
b
c
d
The labels correspond to those used in Figure 2. (SDB-)cc-pVTZ basis set. cc-pVTZ basis set. The hydrogen position was calculated by use of a
riding model; therefore, no error is given.
loss of bond valency that results from the longer Xe---F
consistent with the bent geometry predicted by the VSEPR
bridge and Xe–N bonds. Thus, the total bond valency of Xe
model and with the observed range of Ng---F–As (Ng )
+
34
in F
5
SN(H)Xe (1.206 v.u.) is only 0.050 bond valence unit
Xe, Kr) angles in [XeF][AsF
HF · [HO-TeF -OXe][AsF ] (133.0(4)°),
]·[KrF][AsF
] (128.7(3)° and 126.4(3)°).
Raman Spectroscopy. The Raman spectra of
6
]
(134.8(2)°),
3
5
less than that of the tellurium salt (1.256 v.u.). These
4
6
6
[KrF][AsF ]
32
32
additional long contacts also correlate with closer packing
(133.7(1)°), [Kr
[C Xe][AsF
2 3
F
][AsF
6
6
] (127.5(3)°), and
+
36
in the F
5
SN(H)Xe salt, which is manifested by the smaller
6
F
5
6
crystallographic unit cell volume observed for this salt. The
+
long fluorine contacts to xenon in F
5
SN(H)Xe avoid the
[F
5
SNH
3
][AsF
6
] (Figure 3) and [F
5
SN(H)Xe][AsF
6
] (Figure
3
1
+
11
torus of electron density around xenon(II). These contacts
may also contribute to distortion of the N–Xe---F angle from
4) were assigned by comparison with those of F
5
3
TeNH ,
+
11
+
27,37
38,39
40
5
F TeN(H)Xe ,
F
5
TeOXe ,
SF
6
,
5
and F SCl (Tables
2 3
the expected linear AX E VSEPR arrangement; however,
a similar deviation from linearity was obtained in the energy-
minimized gas-phase geometry (Table S2; see Computational
(32) Lehmann, J. F.; Dixon, D. A.; Schrobilgen, G. J. Inorg. Chem. 2001,
4
0, 3002–3017.
(
33) Fir, B. A.; Gerken, M.; Pointner, B. E.; Mercier, H. P. A.; Dixon,
+
32
Results), and for F–Ng---F (Ng ) Kr or Xe) in Kr
2
F
3
,
D. A.; Schrobilgen, G. J. J. Fluorine Chem. 2000, 105, 159–167.
+
33
32
(34) Zalkin, A.; Ward, D. L.; Biagioni, R. N.; Templeton, D. H.; Bartlett,
Xe F
2 3
,
6
and [KrF][MF ] (M ) As, Sb, or Bi), and
N. Inorg. Chem. 1978, 17, 1318–1322.
therefore may not be wholly attributable to crystal packing.
(
(
35) Turowsky, L.; Seppelt, K. Inorg. Chem. 1990, 29, 3226–3228.
36) Frohn, H.-J.; Klose, A.; Schroer, T.; Henkel, G.; Buss, V.; Opitz, D.;
Vahrenhorst, R. Inorg. Chem. 1998, 37, 4884–4890.
The Xe---F(6)–As bridge bond angle (127.2(1)°) is compa-
1
1
5 6
rable to that in [F TeN(H)Xe][AsF ] (128.1(2)°) and is
(
37) Fir, B. A.; Mercier, H. P. A.; Sanders, J. C. P.; Dixon, D. A.;
Schrobilgen, G. J. J. Fluorine Chem. 2001, 110, 89–107.
(
31) Mercier, H. P. A.; Moran, M. D.; Sanders, J. C. P.; Schrobilgen, G. J.;
(38) Claassen, H. H.; Goodman, G. L.; Holloway, J. H.; Selig, H. J. Chem.
Phys. 1970, 53, 341–348.
Suontamo, R. J. Inorg. Chem. 2005, 44, 49–60.
Inorganic Chemistry, Vol. 47, No. 10, 2008 4177

Smith et al.
Figure 3. Raman spectrum of [F5SNH3][AsF6] recorded at –160 °C using
1
064-nm excitation; symbols denote FEP sample tube lines (*).
Figure 2. (a) X-ray crystal structure of [F5SN(H)Xe][AsF6]; thermal
ellipsoids are shown at the 50% probability level. (b) Calculated geometry
+
of [F5SN(H)Xe][AsF6]. (c) Calculated geometry of the F5SNH3 cation.
4
and 5), and by comparison with the calculated frequen-
cies derived for the gas-phase energy-minimized geometries
+
+
5 3 5 5 6
of F SNH , F SN(H)Xe , and the [F SN(H)Xe][AsF ] ion
Figure 4. Raman spectrum of [F5SN(H)Xe][AsF6] recorded at –45 °C using
064-nm excitation; symbols denote FEP sample tube lines (*), lines arising
from a minor impurity (†), and an instrumental artifact (§).
pair (see Computational Results). The vibrational modes of
1
-
the uncoordinated AsF
6
anion were assigned by com-
4
1
8
parison with those of [O
2
][AsF
], and [F TeNH
of the distorted fluorine-bridged AsF
by comparison with those of [F
6 6
], [HCt NXeF][AsF ],
12
11
[
F
3
St NXeF][AsF
6
5
3
][AsF
6
], and the modes
-
6
anion were assigned
TeN(H)Xe][AsF ],
6
belong to the irreducible representations A1g + E + T2g +
g
1
1
5
2
g
T1u + T2u, where the A1g, E , and T2g modes are Raman-
37
42
43
5 6 6 6
[F TeOXe][AsF ], [XeF][AsF ], and [KrF][AsF ]. Cal-
active and the T1u modes are infrared-active. The formally
Raman-inactive T1u mode was, however, observed in the
culated frequencies appearing in parentheses were obtained
at the MP2/SVWN levels, respectively, except for the ion
pair, which could only be optimized at the SVWN level
–
1
Raman spectrum as a weak band at 387 cm .
The asymmetric NH stretches at 3138 (3524/3310) and
3
(
Table S3). The vibrational frequencies of SF
were chosen as benchmarks for the F S-group frequencies
SN(H)Xe (Table S4; see Computational
6 5
and F SCl
–
1
3
072 (3521/3307) cm , the symmetric NH
3
stretch at 2939
5
–
1
+
+
(3402/3191) cm , and the NH bends at 1560 (1641/1569)
and 1535 (1633/1552) cm–1 were overestimated by the
calculations, which was also observed for F
S–N stretch couples with the equatorial SF
ing mode at 739, 745, 747 cm–1 (757/697 cm ) and with
3
of F
Results).
a) [F
5
SNH
3
and F
5
5 3
TeNH
+. The
11
(
5
SNH ][AsF ]. In the absence of a refined crystal
3
6
4
in-phase breath-
structure, it was not possible to carry out a factor-group
analysis, which might account for the splittings observed on
–1
the majority of the cation and anion Raman bands. The 24
4
the equatorial SF out-of-phase, out-of-plane bend at 576
+
cm–1 (574/508 cm ), contrasting with the Te–N stretch of
–1
vibrational modes of F
5
SNH
3
were assigned under C
1
point
+
symmetry and belong to A irreducible representations, all
F TeNH , which is not significantly coupled. The out-of-
5
3
of which are Raman- and infrared-active. The 15 vibrational
2
phase trans equatorial SF stretching modes are coupled to
–
modes of AsF
6
h
were assigned under O symmetry and
3
NH rocking modes, whereas the axial S–F stretch is not
coupled. All of the bands involving S–F stretches fall into
the range 645–920 cm (669–970/642–924 cm ), and those
(
(
(
(
(
39) Weinstock, B.; Goodman, G. L. AdV. Chem. Phys. 1965, 9, 169–316.
–1
–1
40) Marsden, C. J.; Bartell, L. S. Inorg. Chem. 1976, 15, 3004–3009.
41) Naulin, C.; Bougon, R. J. Chem. Phys. 1976, 64, 4155–4158.
42) Gillespie, R. J.; Landa, B. Inorg. Chem. 1973, 12, 1383–1388.
43) Gillespie, R. J.; Schrobilgen, G. J. Inorg. Chem. 1976, 15, 22–31.
involving SF
5
bending modes occur in the range 362–632
cm–1 (316–613/282–563 cm ), and these have frequencies
–1
4178 Inorganic Chemistry, Vol. 47, No. 10, 2008

F
5
SN(H)Xe+
Table 4. Raman Vibrational Frequencies, Intensities, and Assignments for [F5SNH3][AsF6] and Calculated Vibrational Frequencies and Intensities for
+
F5SNH3
a
b
Values in parentheses denote experimental relative Raman intensities, and abbreviations denote broad (br), shoulder (sh), and not observed (n.o.). cc-pVTZ
basis set. Calculated infrared intensities (in km mol- ) are given in brackets, and calculated Raman intensities (in Å amu ) are given in parentheses. The
atom numbering corresponds to that used in Figure 2, and abbreviations denote out-of-plane (o.o.p.) and in-plane (i.p.) (the plane is defined by the S, N, and
H1 atoms), inversion (inv), twist (Ft), and four equatorial fluorines (F4eq).
1
4
-1
c
–
1
similar to those of SF
6
(615–940 and 347–525 cm ) and
bands expected under C4V symmetry were observed (correlations
to O symmetry are given in square brackets), namely, 681 (A )
and 693, 714 (E) [T ], 598 (B ) and 609 (A ) [E ], 402 (A )
1u 1 1 g 1
–
1
40
F
5
SCl (602–909 and 271–579 cm ). The NH torsion,
3
h
1
–
1
predicted at (4/18 cm ), could not be observed.
+
–1
(
b) [F
5
SN(H)Xe][AsF
6
]. The F
5
SN(H)Xe cation (gas-phase
and 409 (A
group analyses correlating the cation (C
symmetries to their crystal site symmetries (C
1
) [T1u], and 369 (E) and 376 (B
2
) [T2g] cm . Factor-
) and anion (C4V
) and to the unit
and crystallographic symmetries optimized to C
1
symmetry)
1
)
possesses 21 fundamental vibrational modes belonging to A
irreducible representations, which are both Raman- and infrared-
1
cell symmetry (C) are provided in Table S5. The A irreducible
i
active. The fluorine bridge interaction lowered the O
h
symmetry
])
representations of the cation are maintained under C site
symmetry, while the doubly degenerate E modes of the anion
are split as a result of site symmetry lowering. Both the cation
1
of the anion (see X-ray Crystal Structure of [F SN(H)Xe][AsF
5
6
so that additional lines in the vibrational spectra were observed.
Such symmetry lowering in hexafluoro anions of group 15 is
g
and anion modes are split into Raman-active A and infrared-
44
oftentimes approximated as C4V symmetry, and the vibrational
spectra are assigned under this or a lower symmetry (C2V, C
or C ). The distorted anion in the structural unit possesses 15
fundamental vibrational modes under approximate C4V sym-
metry belonging to the irreducible representations 4A + 2B
+ 4E, all of which are Raman-active, and the A and E
modes are infrared-active. In practice, 9 of the 11 vibrational
active A components under C crystal symmetry, giving the
u
i
s
,
potential to observe 21 bands for the cation and 15 bands for
the anion. As predicted, no additional splittings of the 19
observed cation bands and 11 observed anion bands occurred
in the Raman spectrum under the crystal symmetry.
1
1
1
+
B
2
1
The calculated vibrational frequencies for the
+
[
F
5
SN(H)Xe][AsF
6
] ion pair and for the isolated F
5
SN(H)Xe
–
(
44) See ref 32 and references therein.
and AsF
6
ions are generally in good agreement with the
Inorganic Chemistry, Vol. 47, No. 10, 2008 4179

Smith et al.
Table 5. Raman Vibrational Frequencies, Intensities, and Assignments for [F5SN(H)Xe][AsF6], and Calculated Vibrational Frequencies and Intensities
+
for F5SN(H)Xe
a
b
Values in parentheses denote experimental relative Raman intensities, and abbreviations denote broad (br) and not observed (n.o.). (SDB-)cc-pVTZ
basis set. Calculated infrared intensities (in km mol- ) are given in brackets, and calculated Raman intensities (in Å amu ) are given in parentheses. The
1
4
-1
c
atom numbering corresponds to that used in Figure 2, and abbreviations denote in-plane (i.p.) and out-of-plane (o.o.p.; the plane is defined by Xe, N, and
d
S atoms), twist (Ft), wag (Fw), rock (Fr), and four equatorial fluorines (F4eq). Values and mode descriptions are from the calculated ion pair; see Table S3
for a full frequency listing and assignments.
experimental frequencies. The ion pair calculation shows that
the cation and anion modes are not coupled except for the
low-frequency deformation modes. The modes associated
with the Xe---F–As bridge are, however, deemed to be less
reliable because the geometrical parameters of the Xe---F–As
bridge are not well reproduced for the calculated ion pair
assigned by comparison with the modes calculated for the
+
gas-phase F
5
SN(H)Xe cation and, consequently, was as-
signed to ν(Xe---F) by comparison with the frequency
–
1
calculated for the ion pair (420 cm ), with the difference
attributed to the underestimated Xe---F distance. This
frequency is higher than that assigned to ν(Xe---F) in
–
1
5
(
see Computational Results).
[XeN(SO
cm ),
2
F)
2
][AsF ][AsF
6
] (317 cm ), [XeOTeF
5
6
] (365
–1
24,37
–1 42
Coupled ν(SN + XeN) and ν(SN – XeN) stretches were
and [XeF][AsF ] (417 cm ). The Xe–N–S bend
is assigned to the strong band at 151 (136/125) cm , which
is higher than that of the Xe–N–Te bend in F TeN(H)Xe
5
(113 cm ). The highest-frequency band, 3186 cm , is
6
–
1
–1
observed at 520 and 651 (535/512 and 650/586) cm ,
+
respectively, compared with the coupled ν(TeN + XeN) and
+
–1 11
–1
ν(TeN – XeN) stretches observed for F
5
TeN(H)Xe at 444
–
1
11
–1
and 654 cm . The most intense band in the Raman
spectrum of [F SN(H)Xe][AsF ] occurs at 224 (222/207)
cm and is assigned to the Xe–N stretch weakly coupled to
a F S-group rock, whereas the corresponding low-frequency
coupled mode was not observed for the tellurium analogue.
assigned to ν(NH) (3421/3287 cm ) and is in good agree-
+
–1 11
5
6
5
ment with the N–H stretches in F TeN(H)Xe (3146 cm ),
–
1
–1
–1 11
F
F
5
TeNH
2
+
(symmetric, 3297 cm ; asymmetric, 3385 cm ),
–1
–1 11
5
5
TeNH
3
(symmetric, 3018 cm ; asymmetric, 3110 cm ),
+
–1
and F
5
SNH
3
45
(symmetric, 2939 cm ; asymmetric, 3072,
3145 cm ). The δ(SNH) bend, observed at 954 cm , and
δ(NH) wag, which was not observed, were calculated at 980/
–
1
–1
Weak coupling between the Xe–N stretch and F
5
S-group rock
+
of F
5
SN(H)Xe may be the result of the larger mass
–
1
difference between xenon and sulfur than between xenon
and tellurium. The equatorial SF symmetric breathing mode
is weakly coupled with the S–N stretch and occurs at 732
946 and 1328/1230 cm , respectively, and are predicted to
4
be weak. The experimental SF -group stretches (671–904
5
–
1
–1
cm ) and bends (345–631 cm ) fall into ranges that are
–
1
–1
+
cm (737/701 cm ), as observed in F
5
SNH
3
(739, 745,
–
1
–1
and 747 cm ). The broad band at 461 cm could not be
(45) This work.
4180 Inorganic Chemistry, Vol. 47, No. 10, 2008

F
5
SN(H)Xe+
Table 6. Natural Bond Orbital (NBO) Charges, Valencies, and Bond
(127.2(1)°) and is known to be influenced by crystal packing
Orders for F5SNH3 and F5SN(H)Xe+
+
a
b
(
see X-ray Crystal Structure), was significantly more bent
F5SNH3+
F5SN(H)Xe+
charges valencies
atom MP2 SVWN MP2 SVWN MP2 SVWN MP2 SVWN
(
112.7°) for the calculated geometry. Similar differences were
11
charges
valencies
5 6
found for the [F TeN(H)Xe][AsF ] ion pair. It is notewor-
–
thy that the calculated local symmetry of AsF
[F SN(H)Xe][AsF ] ion pair is better approximated by C2V
symmetry than by the local C4V symmetry used to assign
the vibrational frequencies of AsF
Raman Spectroscopy).
6
in the
Xe
H
N
1.01
0.40
0.98 0.57
0.43 0.71
0.61
0.72
1.90
3.91
0.59
0.54
0.54
0.51
0.54
5
6
0.45
-0.85 -0.90 2.39
2.61 2.51 3.67
-0.39 -0.37 0.55
-0.43 -0.42 0.49
-0.43 -0.41 0.49
-0.43 -0.42 0.49
-0.43 -0.41 0.49
0.47 0.63
0.68
2.52 -0.82 -0.82 1.82
3.93 2.58 2.48 3.67
–
6
in the ion pair (see
S
F1
F2
F3
F4
F5
0.61 -0.41 -0.38 0.53
0.55 -0.43 -0.41 0.49
0.54 -0.45 -0.44 0.47
0.55 -0.46 -0.45 0.45
0.54 -0.42 -0.38 0.50
The calculated S–N bond length of F
5
SN(H)Xe+ is
at both levels of
+
significantly shorter than that of F
5
SNH
3
theory. This trend was also observed for the experimental
+
and calculated Te–N bond lengths in F
5
TeN(H)Xe and
bond orders
+
11
+
5 3 5
F TeNH , whereas the S–F bond lengths of F SN(H)Xe
F5SNH3+
F5SN(H)Xe+
MP2 SVWN
are slightly longer (MP2) or slightly shorter (SVWN) than
+
in F
5
SNH
3
. It is not possible to discern significant differ-
bond
MP2
SVWN
ences in either the experimental or calculated Te–F bond
lengths for the tellurium analogues.
Xe-N
N-H
S-N
S-F1
S-F2
S-F3
S-F4
S-F5
0.58
0.71
0.64
0.65
0.60
0.59
0.58
0.62
0.60
0.72
0.68
0.70
0.63
0.64
0.62
0.65
1
1
0.65
0.55
0.67
0.61
0.61
0.61
0.61
0.69
0.56
0.72
0.66
0.66
0.66
0.66
(b) Charges, Valencies, and Bond Orders. The Natural
Bond Orbital (NBO) charges, valencies, and bond orders
calculated using the MP2 and SVWN methods (SVWN
+
values are given in parentheses) for F
5
SNH
3
and
+
a
F
5
SN(H)Xe are listed in Table 6. The formal positive charge
cc-pVTZ basis set; the atom numbering corresponds to that used in
b
Figure 2c. (SDB-)cc-pVTZ basis set; the atom numbering corresponds to
that used in Figure 2b.
of both cations chiefly resides on S, H, and Xe, with positive
+
charges on S and H in F
than the corresponding charges in F
5
SN(H)Xe that are slightly lower
+
5
+
SNH
3
. The Xe–N bond
+
similar to those of F
SCl (vide supra). The medium intensity modes at 108, 119,
and 169 (76, 105, and 156) cm are assigned to strongly
coupled deformation modes associated with the ion pair, but
the torsion about Xe, calculated at 56/45 cm , could not be
observed.
5
SNH
3
and the benchmarks, SF
6
and
order [0.58 (0.60)] in F
5
SN(H)Xe and the decrease in N
F
5
+
+
valency from F
5
SNH
3
[2.39 (2.52)] to F
5
SN(H)Xe [1.82
–
1
(1.90)] also indicate significant covalent bonding between
xenon and nitrogen. Slight decreases in the absolute charges
on sulfur [2.58 (2.48)] and nitrogen [–0.82 (–0.82)] cor-
respond to the greater S–N bond order [0.64 (0.68)] for
–
1
Computational Results. Electronic structure calculations
+
+
F
5
SN(H)Xe when compared with that of F
5
SNH
3
[0.55
+
+
were carried out for
SN(H)Xe][AsF ] to aid in the vibrational assignments (see
Raman Spectroscopy) and to gain insight into the structure
5 3 5
F SNH , F SN(H)Xe , and
(
0.56)] [S charge: 2.61, (2.51); N charge: –0.85 (–0.90)].
[F
5
6
+
The lower N–H bond order of F
compared with that of F
5
SNH
3
[0.65 (0.69)]
+
5
SN(H)Xe [0.71 (0.72)] and parallel
+
+
and bonding of F
the calculated and experimental frequencies with those of
the benchmarks, SF and F SCl, showed that the SVWN
calculations provided vibrational frequencies that were in
better agreement than the MP2 calculations for the highest-
frequency modes, the asymmetric SF
stretches of SF and F SCl, respectively, whereas the MP2
calculations better reproduced the symmetric stretches and
all of the F–S–F bending frequencies (Table S4).
5 3 5
SNH and F SN(H)Xe . Comparisons of
decreases in absolute charges on H and N correspond to
+
increased N–H bond covalency in F
5
SN(H)Xe . There is
6
5
little difference in the S–F bond orders or in the charges
+
and valencies at sulfur and fluorine in F
5
SNH
3
and
+
F
5
SN(H)Xe . The S–Feq bond orders and Feq valencies of
6 4
and equatorial SF
both cations differ little from those of the benchmarks, SF
and F SCl, whereas the S–Fax bond orders and the Fax
6
6
5
5
valencies are slightly higher in both cations.
Conclusions
(
a) Calculated Geometries. Although close to C
s
sym-
+
metry, both the MP2 and SVWN energy-minimized struc-
The F
of XeF
5
SN(H)Xe cation has been synthesized by reaction
+
+
+
tures of the F
symmetry, as did the SVWN energy-minimized structure
of the [F SN(H)Xe][AsF ] ion pair. These calculations
reproduced the experimental geometric parameters of
SN(H)Xe in the ion pair. The largest discrepancies
occurred for the Xe---F–As fluorine bridge of the ion pair.
The Xe---F(6) (2.251 Å) and As–F(6) (1.919 Å) fluorine-
bridge bond lengths are under- and overestimated, respec-
tively, when compared with the experimental values, 2.634(3)
and 1.759(3) Å. The Xe---F–As angle, which was found to
be bent in the low-temperature X-ray crystal structure
5
SNH
3
and F
5
SN(H)Xe cations optimized to
2
with F
5
SNH
3
in BrF
5
and aHF solvents, and by
+
C
1
HF solvolysis of the recently reported F
SN(H)Xe cation provides, in addition to F
(H)Xe , an example of xenon bonded to an sp -hybridized
3
St NXeF cation.
+
5
6
The F
5
+
5
TeN-
3
+
F
5
nitrogen, and the second example of a synthetic route that
+
makes use of an ammonium (F
5
ChNH
3
, Ch ) S or Te)
cation as the synthetic precursor to a Xe–N bonded com-
pound. The Xe–N bond length, calculated Xe–N bond order
1
29
derived from the NBO analyses, high shielding of the Xe
NMR resonance, and empirical Xe–N bond valency derived
from the crystal structure of [F
5 6
SN(H)Xe][AsF ] are con-
Inorganic Chemistry, Vol. 47, No. 10, 2008 4181

Smith et al.
sistent and place F
Xe–N bonded species presently known.
5
SN(H)Xe+ among the most covalent
Crystal Growth. (a) [F
mL) was condensed onto [F St NXeF][AsF ] (0.1186 g, 0.2681
5
SN(H)Xe][AsF
6
]. Anhydrous HF (ca.
1
3 6
mmol) at –196 °C that had been synthesized in situ in one arm of
a ¼-in. o.d. FEP T-shaped reactor fitted with a Kel-F valve. The
reactor was warmed to –78 °C and pressurized to 1 atm with dry
nitrogen before warming to –20 °C, where the reaction was allowed
to proceed for ca. 4 h, over which time the white solid slowly
dissolved and the solution became deep yellow in color. Transparent
yellow plates subsequently grew as the supernatant became color-
less. While maintaining the reactor at –20 °C, the sample was
attached to a vacuum line and the arm containing the solution was
inclined ca. 5° from horizontal inside the glass Dewar of a crystal-
growing apparatus that had been previously adjusted to –20 °C.
The temperature was lowered over a period of 1 h to –50 °C, where
it was held for a further 30 min to allow for more complete
crystallization. Transparent yellow plate-shaped crystals were
isolated by decanting the solvent under dry nitrogen into the sidearm
of the FEP vessel, which was immersed in liquid nitrogen. This
was followed by lowering the sample temperature to –80 °C,
evacuation, and heat-sealing the sidearm containing the supernatant
at –196 °C. The crystalline sample was further dried under a
dynamic vacuum at –80 °C before the crystallization vessel was
back-filled with dry nitrogen and stored at –78 °C until a suitable
crystal could be mounted for a single-crystal X-ray structure
determination.
Experimental Section
Apparatus and Materials. All manipulations were carried out
under strictly anhydrous conditions as previously described.
4
6
47
48
49
Literature methods were used to prepare Nt SF
3
,
AsF
5
,
2
XeF ,
1
2
3 6
and [F St NXeF][AsF ]
and to purify HF (Harshaw Chemical
8
49
5 2
Co.), BrF (Ozark-Mahoning Co.), and SO (Canadian Liquid
5
0
Air, Ltd.).
SNH
perfluorinated polyethylene, polypropylene copolymer) tube, fitted
with a Kel-F valve, was connected to a FEP submanifold that was,
in turn, connected to a stainless steel cylinder containing Nt SF
The cylinder was fitted with two Whitey valves separated by a ca.
-cm length of ¼-in. o.d. stainless steel tubing to produce a volume
ca. 1.4 mL) which could be filled with an autogenous pressure of
Nt SF . Condensation of successive 1.4 mL aliquots of Nt SF
allowed for a total of ca. 0.18 g (1.7 mmol) of Nt SF to be metered
[
F
5
3 6
][AsF ]. In a typical synthesis, a ¼-in. o.d. FEP
(
3
2
3
.
5
(
3
3
3
into the reaction vessel. The reactor was then removed to a metal
vacuum line that was, in turn, connected to a nickel vessel
containing AsF . Excess AsF (2.0 mmol) was condensed into the
5 5
reaction vessel from the calibrated volume of the vacuum manifold
at –196 °C, and the reaction mixture was warmed to –78 °C. The
reaction was allowed to proceed, with occasional mixing, for ca.
(
b) [F
5
SNH
3
][AsF
6
]. Anhydrous HF (ca. 1 mL) was condensed
1
h at –78 °C, forming F
3
St NAsF
5
as a friable white solid. After
by pumping at –78 °C for ca. 1 h, the
onto [F SNH
5
3
][AsF
6
] (0.245 g, 1.70 mmol) at –196 °C that had
removal of the excess AsF
5
been synthesized (vide supra) in situ in one arm of a ¼-in. o.d.
FEP T-shaped reactor fitted with a Kel-F valve. The reactor was
warmed to 0 °C to effect dissolution and initially gave a colorless
solution. The reactor was placed inside the glass Dewar of a crystal-
sample was stored at –78 °C until it was characterized by Raman
spectroscopy. The reactor was then connected to a FEP submanifold
that was, in turn, connected to a Kel-F vessel containing aHF.
3 5
Anhydrous HF was condensed onto F St NAsF at –196 °C, and
32
growing apparatus that had been previously adjusted to 0 °C. This
temperature was maintained, and over a period of 10 h, colorless
plates slowly deposited that were isolated and transferred to a
the reaction vessel was warmed to –78 °C, whereupon the HF
liquified. The reaction mixture was warmed to 0 °C and was allowed
to stand, with occasional mixing, for ca. 6 h, over which time the
white solid dissolved and colorless featherlike crystals of
5
1
goniometer head as previously described.
Crystals of
[
F
5
SNH ][AsF ] were shown, by inspection under a stereomicro-
3
6
5 3 6
[F SNH ][AsF ] were deposited. After the removal of HF under a
scope, to have striations in one plane that are associated with
multiple crystal growth. This was confirmed by a low-angle data
set collection as described below. Although unit cell parameters
were reproducibly determined from six multiple crystals, a )
dynamic vacuum at –78 °C, the sample was stored at that
temperature until it was characterized by Raman spectroscopy.
[
F
5
SN(H)Xe][AsF
was condensed onto [F
in a ¼-in. o.d. FEP reaction tube, fitted with a Kel-F valve, at –196
C. The reaction vessel was initially warmed to –78 °C and then
6
]. In a typical synthesis, ca. 1 mL of aHF
3
St NXeF][AsF ] (0.1309 g, 0.2959 mmol)
6
5
8
.752(1) Å, b ) 5.761(1) Å, c ) 11.733(2) Å, R ) 89.81(1)°, ꢀ )
9.93(1)°, and γ ) 89.74(1)°, only a preliminary solution could
°
be obtained in which bond length uncertainties exceeded 0.02 Å.
This preliminary solution confirmed the expected gross structural
features of the cation and anion and clearly indicated that the axial
bond of the cation was longer than the remaining five bonds. A
to –20 °C and was allowed to stand, with occasional mixing, for
ca. 6 h, over which time the white solid slowly dissolved to form
a yellow solution from which deep-yellow microcrystals deposited.
After removal of the solvent under a dynamic vacuum at –78 °C,
the sample was stored at that temperature until it was characterized
by Raman spectroscopy.
further crystallization attempt from SO
multiple crystals that gave the same unit cell parameters. Attempts
to characterize [F SNH ][AsF ] by single-crystal X-ray diffraction
2
solvent also yielded
+
The F
FEP tube fused to a ¼-in. FEP tube which was fitted with a Kel-F
valve that contained [F SNH ][AsF ] (0.0502 g, 0.1501 mmol) and
a 2-fold excess of XeF (0.0508 g, 0.3003 mmol). Anhydrous HF
or BrF (ca. 0.5 mL) was statically distilled onto the sample at
5
SN(H)Xe cation was also synthesized in a 4-mm o.d.
5
3
6
5
2
have also proven unsuccessful in the hands of other workers.
X-ray Crystallography. (a) Collection and Reduction of
the X-ray Data. A crystal of [F SN(H)Xe][AsF ] having the
5
3
6
2
5
6
3
dimensions 0.28 × 0.24 × 0.10 mm was selected at –105 ( 3 °C for
5
–
196 °C, and the reaction vessel was initially warmed to –78 °C
low-temperature X-ray structure determination and was mounted in a
51
and then to –20 °C just prior to characterization by low-temperature
multi-NMR spectroscopy.
cold stream (–173 °C) on a goniometer head as previously described.
The crystal was centered on a P4 Siemens diffractometer,
equipped with a Siemens SMART 1K charge-coupled device (CCD)
53
(
46) Casteel, W. J., Jr.; Dixon, D. A.; Mercier, H. P. A.; Schrobilgen, G. J.
area detector that used the program SMART, and a rotating anode
Inorg. Chem. 1996, 35, 4310–4322.
(47) Mews, R.; Keller, K.; Glemser, O. Inorg. Synth. 1986, 24, 12–17.
48) Emara, A. A. A.; Lehmann, J. F.; Schrobilgen, G. J. J. Fluorine Chem.
(
(51) Gerken, M.; Dixon, D. A.; Schrobilgen, G. J. Inorg. Chem. 2000, 39,
4244–4255.
(52) Mews, R.; Žemva, B. Private communications.
(53) SMART, release 5.054; SAINT, release 056.001; Siemens Energy and
Automation Inc.: Madison, WI, 1999.
2
005, 126, 1373–1376.
(
(
49) Mercier, H. P. A.; Sanders, J. C. P.; Schrobilgen, G. J.; Tsai, S. S.
Inorg. Chem. 1993, 32, 386–393.
50) Collins, M. J.; Schrobilgen, G. J. Inorg. Chem. 1985, 24, 2608–2614.
4182 Inorganic Chemistry, Vol. 47, No. 10, 2008

F
5
SN(H)Xe+
using graphite-monochromated Mo KR radiation (λ ) 0.710 73 Å).
The diffraction data collection consisted of a full ψ rotation at ꢁ )
and acquisition times of 0.17 s, and were zero-filled to 64K, yielding
data point resolutions of 2.96 Hz/data point. Relaxation delays of 0.10 s
were applied, and 32 000 transients were accumulated.
0
° using (1040 + 40) 0.36° frames, followed by a series of short
(
80 frames) ω scans at various ψ and ꢁ settings to fill the gaps.
Pulse widths, corresponding to a bulk magnetization tip angle
1
19
129
The crystal-to-detector distance was 5.016 cm, and the data
collection was carried out in a 512 × 512 pixel mode using 2 × 2
pixel binning. Processing was carried out by using the program
of approximately 90°, were 2.0 ( H), 8.5 ( F), and 10.0 ( Xe)
1
19
129
µs. Line broadenings of 0 ( H), 0.10 ( F) and 5.0 ( Xe) Hz were
used in the exponential multiplications of the free induction decays
prior to their Fourier transformations.
5
3
SAINT, which applied Lorentz and polarization corrections to
three-dimensionally integrated diffraction spots. The program
The H, F, and 129Xe spectra were referenced externally at 30
1
19
5
4
SADABS was used for the scaling of diffraction data, the
application of a decay correction, and an empirical absorption
correction based on redundant reflections.
°C to samples of neat (CH Si, CFCl , and XeOF , respectively.
3
)
4
3
4
The chemical shift convention used is that a positive (negative)
sign indicates a chemical shift to high (low) frequency of the
reference compound.
(
b) Solution and Refinement of the Structure. The XPREP
Raman Spectroscopy. The low-temperature Raman spectra of
program was used to confirm the unit cell dimensions and the crystal
lattice. The final refinement was obtained by introducing anisotropic
parameters for all the atoms, an extinction parameter, and the
recommended weight factor. The maximum electron densities in
the final difference Fourier maps were located around the heavy
atoms. All calculations were performed with the SHELXTL package
[
F
5
SNH
3
][AsF
6
] (–160 °C) and [F
5 6
SN(H)Xe][AsF ] (–45 °C) were
recorded on a Bruker RFS 100 FT Raman spectrometer using 1064-
nm excitation and a resolution of 1 cm , as previously described.
–1
51
The spectra were recorded using a laser power of 300 mW and a
total of 600 and 10 000 scans, respectively, for acquisition of the
spectra.
5
5
for structure determination, refinement, and molecular graphics.
Computational Methods. Quantum-chemical calculations were
carried out using MP2 and SVWN (DFT) methods and the program
A solution was obtained by direct methods which located the Xe
and As atoms. Successive difference Fourier syntheses revealed
the positions of the fluorine, nitrogen, and sulfur atoms. The position
56
Gaussian 03 for geometry optimizations and vibrational frequen-
+
+
SN(H)Xe+ cation was calculated
cies and intensities for the F
5 3 5
SNH and F SN(H)Xe cations, and
of the hydrogen atom in the F
5
the [F SN(H)Xe][AsF ] ion pair. The standard all-electron cc-pVTZ
5
6
[
d(N–H) ≈ 0.82 Å; U(H) fixed to –1.5U(N)] and was then refined
basis set, as implemented in the Gaussian program, was utilized
for all elements except Xe and As, for which the semirelativistic
using DFIX restraints.
Nuclear Magnetic Resonance Spectroscopy. (a) NMR
57
large core pseudopotential basis set SDB-cc-pVTZ was used. The
combined use of cc-pVTZ and SDB-cc-pVTZ basis sets is indicated
Sample Preparation. Samples of [F
H)Xe][AsF ] (ca. 50 mg each) were prepared in 4-mm o.d. FEP
tubes fused to ¼-in. FEP tubing which were fitted with Kel-F valves
that contained F St NAsF (41 mg) and [F St NXeF][AsF ] (48
5 3 6 5
SNH ][AsF ] and [F SN-
(
6
5
8
by (SDB-)cc-pVTZ. The program GaussView was used to
visualize the vibrational displacements that form the basis of the
vibrational mode descriptions given in Tables 4, 5, and S3.
3
5
3
6
mg), respectively. The NMR tubes were connected to a FEP
submanifold that was, in turn, connected through a Kel-F valve to
a Kel-F storage vessel containing aHF. The FEP submanifold was
connected to a metal vacuum line, and ca. 0.5 mL of aHF was
statically distilled onto the starting materials at –196 °C. The NMR
samples were then heat-sealed under dynamic vacuum and stored
at –196 °C until their NMR spectra could be obtained. Samples
were dissolved just prior to data acquisition at or below the
temperature used to record their spectra. When obtaining low-
temperature spectra, the 4-mm o.d. FEP tubes were inserted into a
Acknowledgment. We thank the Natural Sciences and
Engineering Research Council (NSERC) of Canada for
financial support in the form of a research grant (G.J.S.);
the Ontario Ministry of Training, Colleges and Universities
and the McMaster University Centennial Scholarship Fund
for the award of graduate scholarships (G.L.S.); Dr. J. C. P.
Sanders and N. T. Arner for preliminary NMR work; and
SHARCNet (Shared Hierarchical Academic Research Com-
puting Network; www.sharcnet.ca) for computational re-
sources.
5
-mm o.d. thin-wall precision glass NMR tube (Wilmad).
(
b) NMR Instrumentation and Spectral Acquisitions. Proton,
1
9
129
F, and Xe nuclear magnetic resonance spectra were recorded
–
1
unlocked (field drift <0.1 Hz h ) on a Bruker DRX-500 spec-
trometer equipped with an 11.744-T cryomagnet. The NMR probe
was cooled using a nitrogen flow and variable-temperature controller
(55) SHELXTL-Plus, release 5.1; Siemens Analytical X-ray Instruments,
Inc.: Madison, WI, 1998.
(
56) Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Scuseria, G. E.; Robb,
M. A.; Cheeseman, J. R.; Zakrzewski, V. G.; Montgomery, J. A., Jr.;
Stratmann, R. E.; Burant, J. C.; Dapprich, S.; Millam, J. M.; Daniels,
A. D.; Kudin, K. N.; Strain, M. C.; Farkas, O.; Tomasi, J.; Barone,
V.; Cossi, M.; Cammi, R.; Mennucci, B.; Pomelli, C.; Adamo, C.;
Clifford, S.; Ochterski, J.; Petersson, G. A.; Ayala, P. Y.; Cui, Q.;
Morokuma, K.; Salvador, P.; Dannenberg, J. J.; Malick, D. K.; Rabuck,
A. D.; Raghavachari, K.; Foresman, J. B.; Cioslowski, J.; Ortiz, J. V.;
Baboul, A. G.; Stefanov, B. B.; Liu, G.; Liashenko, A.; Piskorz, P.;
Komaromi, I.; Gomperts, R.; Martin, R. L.; Fox, D. J.; Keith, T.; Al-
Laham, M. A.; Peng, C. Y.; Nanayakkara, A.; Challacombe, M.; Gill,
P. M. W.; Johnson, B.; Chen, W.; Wong, M. W.; Andres, J. L.;
Gonzalez, C.; Head-Gordon, M.; Replogle, E. S.; Pople, J. A. Gaussian
(
BVT 3000).
1
9
1
The F ( H) NMR spectra were acquired using a 5-mm
1
19
combination H/ F probe operating at 470.592 (500.138) MHz.
The spectra were recorded in 32K memories, with spectral width
settings of 24 (6.8) kHz and acquisition times of 1.39 (2.42) s,
and were zero-filled to 64K, yielding data point resolutions of
0
.36 (0.21) Hz/data point. Relaxation delays of 0.10 (2.5) s were
applied, and 1600 (8) transients were accumulated.
The 129Xe NMR spectra were obtained using a 5-mm broad-
band inverse probe operating at 138.086 MHz. The spectra were
recorded in 32K memories, with spectral width settings of 97.1 kHz
9
8, revision A.11; Gaussian, Inc.: Pittsburgh, PA, 2003.
(57) Basis sets were obtained from the Extensible Computational Chemistry
Environment Basis set Database, version 2/25/04, as developed and
distributed by the Molecular Science Computing Facility, Environ-
mental and Molecular Science Laboratory, which is part of the Pacific
Northwest Laboratory, P.O. Box 999, Richland, WA 99352.
(
54) Sheldrick, G. M. SADABS (Siemens Area Detector Absorption
Corrections); University of Göttingen: Göttingen, Germany. Personal
communication, 1998.
(58) GaussView, release 3.0; Gaussian Inc.: Pittsburgh, PA, 2003.
Inorganic Chemistry, Vol. 47, No. 10, 2008 4183

Smith et al.
–
Supporting Information Available: Bond valencies for
SN(H)Xe][AsF ] and [F TeN(H)Xe][AsF ] (Table S1); experimental
and calculated bond lengths and angles for the [F SN(H)Xe][AsF
ion pair (Table S2); experimental and calculated vibrational frequencies,
intensities, and assignments for the [F SN(H)Xe][AsF ] ion pair (Table
S3); experimental and calculated geometric parameters, vibrational
frequencies, assignments, and calculated NBO data for SF and F SCl
(Table S4); factor-group analyses for F
5
SN(H)Xe+ and AsF
6
in
19
[
F
5
6
5
6
5 6 5 3 6
[F SN(H)Xe][AsF ] (Table S5); F NMR spectrum of [F SNH ][AsF ]
Figure S1); and an X-ray crystallographic file in CIF format for the
structure determination of [F SN(H)Xe][AsF ]. This material is avail-
5
6
]
(
5
6
5
6
able free of charge via the Internet at http://pubs.acs.org.
IC702039F
6
5
4184 Inorganic Chemistry, Vol. 47, No. 10, 2008