Single-crystal structure determination of NO2SbF6, XeF5SbF6 and XeF5Sb2F11

Article abstract of DOI:10.1016/j.jfluchem.2015.03.004

NO₂SbF₆ crystalizes at 150 K in the orthorhombic Cmmm space group (No. 65) with a = 6.8119(7) ?, b = 7.3517(7) ?, c = 5.5665(5) ?, V = 278.77(5) ?³, and Z = 2. Its crystal structure exhibits a different packing of the [NO₂]⁺ and [SbF₆]^- ions than in the known crystal structure of NO₂AsF₆. The XeF₅SbF₆ compound is orthorhombic at 150 K, space group Pnma (No. 62), with a = 16.7159(6) ?, b = 8.1093(3) ?, c = 5.7576(2) ?, V = 780.47(5) ?³, Z = 4, and it is isotypic with the known XeF₅MF₆ crystal structures of M = Nb, Ru, and Pt. The unit cell of XeF₅Sb₂F₁₁ is triclinic at 200 K, P1ˉ space group (No. 2), with a = 8.5223(8) ?, b = 8.5582(8) ?, c = 9.2012(8) ?, α = 68.799(8)°, β = 74.897(8)°, γ = 76.252(8)°, V = 596.35(10) ?³ and Z = 2. Each [XeF₅]⁺ cation has four interactions with the three [Sb₂F₁₁]^- anions.

Full text of DOI:10.1016/j.jfluchem.2015.03.004

Journal of Fluorine Chemistry 175 (2015) 47–50
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Journal of Fluorine Chemistry
journal homepage: www.elsevier.com/locate/fluor
Single-crystal structure determination of NO2SbF6, XeF5SbF6 and
XeF5Sb2F11
*
Zoran Mazej , Evgeny A. Goreshnik
ˇ
Jozef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia
A R T I C L E I N F O
A B S T R A C T
NO2SbF6 crystalizes at 150 K in the orthorhombic Cmmm space group (No. 65) with a = 6.8119(7) A,
˚
Article history:
3
Received 25 February 2015
Received in revised form 11 March 2015
Accepted 16 March 2015
Available online 24 March 2015
˚
˚
˚
b = 7.3517(7) A, c = 5.5665(5) A, V = 278.77(5) A , and Z = 2. Its crystal structure exhibits a different
packing of the [NO2]+ and [SbF6]ꢀ ions than in the known crystal structure of NO2AsF6. The XeF5SbF6
˚
˚
compound is orthorhombic at 150 K, space group Pnma (No. 62), with a = 16.7159(6) A, b = 8.1093(3) A,
3
˚
˚
c = 5.7576(2) A, V = 780.47(5) A , Z = 4, and it is isotypic with the known XeF5MF6 crystal structures of
¯
M = Nb, Ru, and Pt. The unit cell of XeF5Sb2F11 is triclinic at 200 K, P1 space group (No. 2), with
Keywords:
˚
˚
˚
a = 8.5223(8) A, b = 8.5582(8) A, c = 9.2012(8) A,
a
= 68.799(8)8,
b
= 74.897(8)8,
g
= 76.252(8)8,
Xenon
V = 596.35(10) A and Z = 2. Each [XeF5]+ cation has four interactions with the three [Sb2F11
]
anions.
3
ꢀ
˚
Antimony pentafluoride
Nytril
ß 2015 Elsevier B.V. All rights reserved.
Crystal structure
Single crystals of XeF5SbF6, XeF5Sb2F11 and NO2SbF6 were
grown during attempts to prepare analog mixed-cation com-
pounds such as NO2XeF5(SbF6)2 [21] with other cations. Their
crystal structures were determined and are described in the
present paper.
1. Introduction
In 1964, Gard and Cady reported on the preparation and some of
the properties of Xe2F11SbF6, XeF5SbF6 and XeF5Sb2F11 [1].
XeF5SbF6 was also investigated by 19F NMR spectroscopy in an
anhydrous hydrogen solution [2]. According to the available
literature there are twelve known compounds of the type XeF5MF6
(M = V [3], Nb [4], Ta [5], Ru [6], Ir [7], Os [8], Pt [9], Au [8], As [10],
Sb [1], Bi [11] and U [12]). In some reviews [XeF5]+[PdF6]ꢀ with
Pd(V) is mentioned [13–15]. However, this must be a typographical
error, since an inspection of the original literature shows that in
reality [XeF5]2+[PdF6]2ꢀ with Pd(IV) was reported [16,17].
In contrast to the XeF5MF6 phases (XeF6:MF5 = 1:1) there are
only two compounds known with a 1:2 ratio (i.e., XeF5M2F11).
XeF5V2F11 is only stable under its own vapor pressure, without
decomposition at least to its melting point (39 ꢁ 1 8C) [3].
XeF5Sb2F11 has a melting point of 108 ꢁ 1 8C [1]. A saturated solution
of XeF5Sb2F11 in BrF5 was investigated using 19F NMR spectroscopy
[2], while the solid compound was studied by Mo¨ssbauer spectros-
copy [18].
2. Experimental
2.1. Apparatus, techniques and reagents
The volatile materials (anhydrous HF, F2, SbF5, NO2F) were
handled in a nickel vacuum line and an all-PTFE vacuum system
equipped with PTFE valves, as previously described [22]. The non-
volatile materials were manipulated in a dry-box (M. Braun,
Germany) in which the residual water in the atmosphere never
exceeded 1 ppm. The reactions were carried out in FEP (tetra-
fluoroethylene-hexafluoropropylene; Polytetra GmbH, Germany)
reaction vessels (height 250–300 mm with an inner diameter of
15.5 mm and an outer diameter of 18.75 mm) equipped with PTFE
valves [23] and PTFE-coated stirring bars. Prior to their use, all the
reaction vessels were passivated with elemental fluorine (Solvay).
The SbF5, NO2SbF6 and XeF5SbF6 were prepared as described
previously [21]. Anhydrous HF (Linde, Fluorwasserstoff 3.5) was
treated with K2NiF6 (Ozark-Mahoning, 99%) for several hours prior
to its use. The xenon difluoride was prepared by a photochemical
reaction between Xe and F2 at ambient temperature [24]. The
H3OSbF6 and XeFSbF6 were synthesized in a reaction between H2O
and XeF2, respectively, and an equimolar amount of SbF5 in aHF.
The synthesis and vibrational data are available for NO2SbF6
[19,20] but there is no information about its crystal structure.
*
Corresponding author. Tel.: +386 1 477 3301.
E-mail address: zoran.mazej@ijs.si (Z. Mazej).
http://dx.doi.org/10.1016/j.jfluchem.2015.03.004
0022-1139/ß 2015 Elsevier B.V. All rights reserved.

48
Z. Mazej, E.A. Goreshnik / Journal of Fluorine Chemistry 175 (2015) 47–50
Table 1
DIAMOND 3.1 [30] and Balls & Sticks (freely available) software
[31].
Summary of the crystal-data and refinement results for NO2SbF6, XeF5SbF6 and
XeF5Sb2F11
.
More details about the crystal-structure investigations may be
obtained from Fachinformationszentrum Karlsruhe, 76344 Eggen-
stein-Leopoldshafen, Germany (fax: +49 7247 808 666; e-mail:
crysdata@fiz-karlsruhe.de, http://www.fiz-karlsruhe.de) by quot-
ing the deposition numbers CSD-429243 (NO2SbF6), CSD-429244
(XeF5SbF6) and CSD-429245 (XeF5Sb2F11).
Formula
NO2SbF6
150
XeF5SbF6
150
XeF5Sb2F11
200
T (K)
Crystal system
Space group
Orthorhombic
Cmmm
6.8119(7)
7.3517(7)
5.5665(5)
/
Orthorhombic
Pnma
Triclinic
¯
P1
˚
a (A)
16.7159(6)
8.1093(3)
5.7576(2)
/
8.5223(8)
8.5582(8)
9.2012(8)
68.799(8)
74.897(8)
76.252(8)
596.35(10)
2
˚
b (A)
˚
c (A)
a
b
g
(8)
(8)
(8)
/
/
/
/
3. Results and discussion
3
˚
V (A )
278.77(5)
2
780.47(5)
4
Z
Details of the data-collection parameters and other crystallo-
graphic information about NO2SbF6, XeF5SbF6 and XeF5Sb2F11 are
provided in Table 1.
Dcalcd (g/cm3)
3.3563
0.71073
5.031
3.9317
0.71073
7.957
3.7798
˚
l
m
(A)
0.71073
7.513
(mmꢀ1
)
GOF indicatora
0.984
1.046
1.033
b
R1
0.034
0.022
0.029
3.1. Crystal structure of NO2SbF6
c
wR2
0.088
0.055
0.067
a
GOF = [
S
w(F02 ꢀ Fc2)2/(No ꢀ Np)]1/2, where No = no. of reflns and Np = no. of refined
It was surprising to find that the crystal structures of NO2AsF6
and NO2SbF6 are not isotypic. The former crystallizes in the
monoclinic C2/m space group (No. 12) at 291 K [32] and the latter
in the orthorhombic Cmmm space group (No. 65) at 150 K. The
crystal structures differ in terms of the packing of the XF6 (X = As,
Sb) octahedra and the positions of the [NO2]+ cations (Fig. 1).
However, in both structures the nitrogen atoms of the [NO2]+
cations have four equal contacts to the fluorine atoms of the four
[XF6]ꢀ anions (Fig. 2).
parameters.
b
R1
=
S
jjFoj ꢀ jFcjj/ jFoj.
S
c
wR2 = [S
w(F02 ꢀ Fc2)2/S(w(F02)2]1/2
.
The O2SbF6 was synthesized by a reaction between SbF5, F2 and O2
in aHF as a solvent in the presence of a UV-source (450 W,
immersion-type photochemical lamp, Ace Glass Inc., USA).
All the atoms in NO2SbF6 occupy special positions. The oxygen
atoms of the cation lie at the 4j Wyckoff position with m2m site
symmetry, and the nitrogen atoms occupy the 2d position with
mmm symmetry. The NꢀO bond lengths in the NO2SbF6 are shorter
2.2. Crystal growth of XeF5SbF6, XeF5Sb2F11 and NO2SbF6
A T-shaped apparatus consisting of two FEP tubes (6 mm and
19 mm outer diameters) was used for the single-crystal growth.
The solids were loaded (approximately 150 mg) into the wider arm
of the crystallization vessel in a dry-box. The aHF (4 ml) was then
condensed onto the starting material at 77 K. The crystallization
mixture was brought up to ambient temperature and the clear
solution that had developed, was decanted into the narrower arm.
The evaporation of the solvent from this solution was carried out
by maintaining a temperature gradient corresponding to about
10 K between both tubes for two months. The effect of this
treatment was to enable the aHF to be slowly evaporated from the
narrower into the wider tube, leaving behind the crystals. Single
crystals of NO2SbF6 were grown during the attempt to prepare the
(NO2)(XeF)(SbF6)2 compound as in the case of Xe(VI) where
NO2XeF5(SbF6)2 [21] was synthesized. In a similar attempt to
˚
˚
(1.111(8) A at 150 K) than those in the NO2AsF6 (1.159(3) A at
291 K) [32] and are comparable to those observed in NO2Xe2F13
˚
˚
(1.10–1.12 A at 130 K) [33], (NO2)2ReF8 (1.1164 A at 125ꢀK) [34]
˚
and NO2ReOF6 (1.085–1.14 A at 132 K) [35]. The [SbF6] anion
geometry is also restricted by symmetry: each SbF6 moiety
contains only two crystallographically independent fluorine atoms
located at the 8o (m symmetry) and 4j (m2m) positions,
respectively, resulting together with the 2b (mmm) Wyckoff
position of the Sb atom in a pair of equal Sb1–F2 and four identical
Sb1–F1 bonds.
prepare unknown (H3O)XeF5(SbF6)2 by
a reaction between
H3OSbF6 and XeF5SbF6 only single crystals of the latter were
found between the powdered material. The crystallization of the
O2SbF6/XeF5SbF6 mixture yields only single crystals of XeF5Sb2F11
instead of the desired unknown O2XeF5(SbF6)2.
The crystallization products were immersed in perfluorinated
oil (Fluorchem, melting point 263 K) in a dry-box. The single
crystals were then selected from the crystallization products under
the microscope outside the dry-box and then transferred into the
cold nitrogen stream of the diffractometer.
2.3. Crystal structure determination of XeF5SbF6, XeF5Sb2F11 and
NO2SbF6
Single-crystal data for all three compounds were collected on a
Gemini A diffractometer equipped with an Atlas CCD detector,
using graphite monochromated MoK
a radiation. The data were
treated using the CrysAlis software suite program package [25].
The structures were solved with the charge-flipping method using
the Superflip [26] program (Olex crystallographic software [27])
and refined with the SHELXL-2013 [28] software, implemented in
program package WinGX. [29]. The figures were prepared using the
Fig. 1. Part of the crystal structure of NO2SbF6 (a, c) showing packing of the [NO2]+
and [SbF6]ꢀ ions. For comparison, the packing of the [NO2]+ and [AsF6]ꢀ in NO2AsF6
(b, d) is also given. [32].

Z. Mazej, E.A. Goreshnik / Journal of Fluorine Chemistry 175 (2015) 47–50
49
Fig. 2. Perpendicular view of part of the layer (in the bc plane) in the crystal
structure of the NO2SbF6 showing the interactions of the [NO2]+ cations with the
[SbF6]ꢀ anions; thermal ellipsoids are drawn at the 50% probability level.
ꢀ
Fig. 4. Packing of [XeF5]+ cations and [Sb2F11
XeF5Sb2F11
]
anions in the crystal structure of
.
Fig. 5. Part of the crystal structure of XeF5Sb2F11 showing the interactions between
ꢀ
the [XeF5]+ cation and the three [Sb2F11
the 50% probability level.
] anions; thermal ellipsoids are drawn at
Fig. 3. Part of the crystal structure of the XeF5SbF6 showing the interactions
between the [XeF5]+ cation and the [SbF6]ꢀ anions; thermal ellipsoids are drawn at
the 50% probability level.
compound has been well described in previous X-ray crystallo-
graphic studies and requires no further discussion. The interac-
tions between the [XeF5]+ and [SbF6]ꢀ ions are shown in Fig. 3 and
the selected bond distances are given in Table 2. The XeꢀF bond
lengths of the [XeF5]+ cation are similar to those determined in
[XeF5][SbF6]ꢂXeOF4 at 151 K [36].
Four secondary Nꢂ ꢂ ꢂF contacts in the NO2SbF6 are equal to
˚
2.540(4) A and comparable to the Nꢂ ꢂ ꢂF contacts in the other
[NO2]+ fluorides [32–35]. The four equatorial SbꢀF1 bonds
involved in the secondary bonding with the N are slightly
˚
elongated (1.879(4) A) in comparison to the remaining SbꢀF2
˚
bonds (1.865(7) A).
3.2. Crystal structure of XeF5SbF6
The XeF5SbF6 single-crystal determination revealed that the
compound is isotypic to the known XeF5MF6 (M = Ru [6], Pt [9]) as
previously suggested on the basis of the X-ray powder diffraction
data [11]. Both, the cation and the anion are located at mirror
planes. In each XeF5 unit the Xe1 and F1 atoms reside on special 4c
positions resulting in one Xe1–F1, two Xe1–F2 and two Xe1–F3
distances. Four fluorine atoms (F4, F5, F6, F8) together with the Sb
atom are located at the mirror plane and the remaining F7 occupies
a general position (Fig. 3). This structural type of XeF5MF6
Table 2
˚
Selected distances, Xeꢂ ꢂ ꢂF contacts (A) and angles (8) in the crystal structure of
XeF5SbF6.
Sb1–F4
Sb1–F5
Sb1–F6
Sb1–F7
Sb1–F8
1.895(3)
1.857(3)
1.859(3)
2 ꢃ 1.882(2)
1.898(3)
Xe1–F1
Xe1–F2
Xe1–F3
Xe1ꢂ ꢂ ꢂF4
Xe1ꢂ ꢂ ꢂF7
Xe1ꢂ ꢂ ꢂF8
1.804(3)
2 ꢃ 1.841(2)
2 ꢃ 1.844(2)
2.617(3)
Fig. 6. Part of the crystal structure of XeF5Sb2F11 showing the interactions between
2 ꢃ 2.860(2)
2.638(3)
ꢀ
]
anion and the three [XeF5]+ cations; thermal ellipsoids are drawn at
the [Sb2F11
the 50% probability level.

50
Z. Mazej, E.A. Goreshnik / Journal of Fluorine Chemistry 175 (2015) 47–50
Table 3
The crystal structure of XeF5Sb2F11 represents the only known
example of XeF6:MF5 = 1:2 compound.
˚
Selected distances (A) and angles (8) in the crystal structure of XeF5Sb2F11
.
Xe–F1
1.803(3)
1.830(3)
1.832(3)
1.834(3
1.835(3)
2.915(3)
2.848(3)
2.775(3)
2.814(3)
1.838(3)
1.846(3)
1.853(3)
1.866(3)
Sb1–F10
Sb1–F11
Sb2–F11
Sb2–F12
Sb2–F13
Sb2–F14
Sb2–F15
Sb2–F16
1.883(3)
2.019(3)
2.029(3)
1.837(3)
1.838(3)
1.843(3)
1.870(3)
1.878(3)
Xe–F2
Acknowledgement
Xe–F3
Xe–F4
Xe–F5
The authors gratefully acknowledge the financial support from
the Slovenian Research Agency (ARRS) within the research
program: P1-0045 Inorganic Chemistry and Technology.
Xeꢂ ꢂ ꢂF9
Xeꢂ ꢂ ꢂF10
Xeꢂ ꢂ ꢂF15
Xeꢂ ꢂ ꢂF16
Sb1–F6
Sb1–F7
Sb1–F8
Sb1–F9
Appendix A. Supplementary data
Sb2F11 angles
Sb1–Fb–Sb2a
Torsion angleb
145.09(16)
Supplementary data associated with this article can be found, in the
online version, at http://dx.doi.org/10.1016/j.jfluchem.2015.03.004.
ꢄ37.5
a
Bending of two SbF5 groups about Fb (bridging fluorine) which is expressed in
terms of the bridge angle
b
a.
Torsion of two planar SbF4,eq groups from eclipsed to staggered conformation
expressed as the torsion angle ( ) [37,38].
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c
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of [XeF5]+ is similar to that of XeF5SbF6, i.e. the Xe–Fax is shorter
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ˇ
ˇ
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]
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ˇ
[23] PTFE valves were constructed and made at Jozef Stefan Institute in a similar way
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The crystal structures of twelve known XeF5MF6 (M = V, Nb, Ta, Ru,
Ir, Os, Pt, Au, As, Sb, Bi and U) compounds, where for M = Nb [4], Ru [6],
Pt [9], As [10], Sb, Au [8] and U [12] the crystal structures were
determined on single-crystal data, can be divided into three groups. In
the first group there are the As and Au compounds. In the second are
the Nb, Ru, Pt, Sb and according to X-ray powder diffraction data also
the Ta [5,39], Ir [7,8] and Os [8] compounds. The uranium compound
is the only example of the third group; meanwhile no structural
information is available for the V [3] or the Bi compound [11].
The crystal structures of the NO2AsF6 (determined at 291 K)
[32] and NO2SbF6 (determined at 150 K) are not isotypic. They
differ in terms of packing of the XF6 (X = As, Sb) octahedra and
locations of the [NO2]+ cations. In the future it would be interesting
to check whether there is a possible phase transition and what is
the situation with the NO2MF6 crystal structures consisting of
[MF6]ꢀ anions of similar size, i.e. M = Nb, Ta, Au, etc.
ˇ
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