The Tetrachloridoaurates(III) of Zinc(II) and Cadmium(II)

Article abstract of DOI:10.1002/zaac.201700455

The first salt-like compounds of dications with [AuCl₄]^– anions are reported. The compounds Zn[AuCl₄]₂·(AuCl₃)_1.115 (1) and Cd[AuCl₄]₂ (2) are obtained from reactions of MCl₂ (M = Zn, Cd) and elemental gold in liquid chlorine at ambient temperature under autogenous pressure and subsequent annealing at 230 °C. The structure of 1 represents an incommensurately modulated composite [superspace group C2/c(α0γ)0s] built of two subsystems. The first subsystem contains chains of zinc(II) tetrachloridoaurate(III), which feature a slightly distorted octahedral coordination of Zn and can be described by the Niggli formula ¹_∞{Zn[AuCl₄]_1/1[AuCl₄]_2/2}. The second subsystem consists of Au₂Cl₆ molecules, which are located in channels built up by the first subsystem. The structural parameters of the hosted Au₂Cl₆ molecules show only small deviations from neat AuCl₃. The crystal structure of Cd[AuCl₄]₂ (2) consists of chains built of Cd²⁺ ions coordinated by bridging [AuCl₄]^– anions and alternating Cd-Au sequence. Cd has a distorted octahedral coordination environment.

Full text of DOI:10.1002/zaac.201700455

Title: The Tetrachloridoaurates(III) of Zinc(II) and Cadmium(II)
Authors: Johannes Beck and Christian Landvogt
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To be cited as: Z. anorg. allg. Chem. 10.1002/zaac.201700455
Link to VoR: http://dx.doi.org/10.1002/zaac.201700455

10.1002/zaac.201700455
Zeitschrift für anorganische und allgemeine Chemie
ARTICLE
The Tetrachloridoaurates(III) of Zinc(II) and Cadmium(II)
Christian Landvogt[a] and Johannes Beck*[a]
Dedicated to Prof. Hartmut Bärnighausen on the Occasion of his 85. Birthday
Abstract: The first salt-like compounds of dications with [AuCl4]−
anions are reported. The compounds Zn[AuCl4]2·(AuCl3)1.115 (1) and
Cd[AuCl4]2 (2) are obtained from reactions of MCl2 (M = Zn, Cd) and
elemental gold in liquid chlorine at ambient temperature under
autogenous pressure and subsequent annealing at 230 °C. The
structure of 1 represents an incommensurately modulated composite
(superspace group C2/c(α0γ)0s) built of two subsystems. The first
subsystem contains chains of zinc(II) tetrachloridoaurate(III), which
found to have an incommensurately modulated composite
structure.
Results and Discussion
The properties and crystal structure of Zn[AuCl4]2·(AuCl3)1.115 (1)
feature a slightly distorted octahedral coordination of Zn and can be
Zn[AuCl4]2·(AuCl3)1.115 (1) forms air-sensitive transparent orange
crystals. DSC measurements heating up from -50 °C show no
thermal effect up to the decomposition of the compound at about
250 °C, which coincidences with the decomposition temperature
of neat AuCl3. The single crystal diffraction pattern of this
compound cannot be fully indexed with three indices hkl.
However, hklm indexing as a 3+1D modulated compound
succeeded. Additionally, Fourier maps from initial structure
solution attempts suggested that the crystal is best described as
an incommensurately modulated composite crystal with two
subsystems in the monoclinic superspace group C2/c(α0γ)0s.
Table 3 holds the crystallographic data for 1, unit cell data for
both subsystems is shown in Table 4. Further details are
available in the Supporting Information.
ퟏ
{
[
]
[ ] }
AuCl4 . The
2/2
described by the Niggli formula
Zn AuCl4
∞
1/1
second subsystem consists of Au2Cl6 molecules, which are located
in channels built up by the first subsystem. The structural
parameters of the hosted Au2Cl6 molecules show only small
deviations from neat AuCl3. The crystal structure of Cd[AuCl4]2 (2)
consists of chains built of Cd2+ ions coordinated by bridging [AuCl4]–
anions and alternating Cd-Au sequence. Cd has
octahedral coordination environment.
a distorted
Introduction
Gold(III) halides are Lewis acids and readily form salts with alkali
halides. A large number of salts with alkali cations have been
reported [1]. However, the number of known compounds for
salts with dications is dramatically smaller. Only salts of
tetrafluoridoaurate(III) anions with alkaline earth and divalent
transition metal cations (M[AuF4]2 with M = Mg, Ba, Ni, Pd, Ag,
Au, Zn, Cd, Hg) have been reported [2], but compounds of the
heavier halogen homologues of the formula type M[AuX4]2 with
The first subsystem contains zinc(II) tetrachloridoaurate(III), the
second subsystem contains gold(III) chloride in form of discrete
Au2Cl6 molecules. The asymmetric unit of the first subsystem
consists of one zinc atom and two halves of the anion, the
asymmetric unit of the second subsystem contains one gold
atom and a terminal and a bridging chlorine atom, respectively.
The zinc(II) tetrachloridoaurate(III) substructure forms chains,
which run along the (101) direction (Figure 1). In these chains,
zinc(II) is coordinated by three tetrachloridoaurate anions, which
act as mono- or bis-chelating ligands resulting in a distorted
octahedral ZnCl6 coordination sphere. One of the [AuCl4]– anions
is coordinated terminally, while the other two are bridging
between Zn cations, resulting in zig-zag chains with alternating
Zn-Au sequence. The Zn-Cl distances for the three surrounding
anions differ slightly. The shortest distance is present between
the chlorine atoms of the terminal [AuCl4]– anions and the Zn2+
cations (roughly 2.40 Å), while the bridging [AuCl4]– ligands are
slightly farther away from the Zn2+ cations (Zn-Cl distances
between 2.46 Å and 2.52 Å). The distortion of the octahedron is
reflected best by its Cl-Zn-Cl angles, which range from 80° to
100° and thus deviate substantially from rectangularity.
X = Cl, Br, or
I are unknown. The literature holds two
compounds, which come close to this formula type. In 1988
Jones et al. reported a zinc(II) tetrachloroaurate disolvate [3] and
more recently, in 2007, the tetraamminepalladium salt
[Pd(NH3)4][AuCl4]2 was reported by Plyusnin et al. [4]. However,
in both compounds additional ligands are present in the
coordination sphere of the respective dication besides the
chloride anions of the tetrachloridoaurate(III) anion. Looking for
even higher charged cations a single exception is again found
for tetrafluoridoaurate(III). In 1996 Graudejus et al. reported the
synthesis and crystal structure of La[AuF4]3 [5].
This work describes the synthesis and the crystal structures of
the first salts of tetrachloridoaurate(III) with dications:
Zn[AuCl4]2·(AuCl3)1.115 (1) and Cd[AuCl4]2 (2). Compound 1 is
*
Prof. Dr. J. Beck
Fax: +49-228-735660
E-Mail: j.beck@uni-bonn.
Institut für Anorganische Chemie
Gerhard-Domagk-Str. 1
53121 Bonn, Germany
[a]
Supporting information for this article is available on the WWW
under http://dx.doi.org/xxxxxxxx or from the author.
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10.1002/zaac.201700455
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ARTICLE
Figure 3. Au2Cl6 molecules taken from the crystal structure of 1 at t = 0. The
channel built by subsystem I is slightly too large, the molecules are oriented in
different directions. The Cl(6)···Cl(6) distances between adjacent molecules
are a function of t (Figure 4). Symmetry codes for equivalent atoms have been
omitted. The displacement ellipsoids represent a probability of 90 %.
Figure 1. Section of the zinc(II) tetrachloroaurate(III) chain taken from the
crystal structure of 1 at t = 0. The chain runs along the (101) direction and can
ퟏ
∞
{
[
]
[
] }
. Symmetry codes
2/2
be described by the Niggli formula Zn AuCl4
AuCl4
1/1
for equivalent atoms have been omitted. The displacement ellipsoids
represent a probability of 90 %.
The arrangement of the zig-zag chains builds up a honeycomb-
like structure when viewed along the crystallographic c axis. This
honeycomb structure generates flat channels within the crystal
packing running along the c axis (see Figure 2). These channels
are filled by the second subsystem.
Figure 4. t-Plot of the distance between the terminal chlorine atom of adjacent
Au2Cl6 molecules in the modulated crystal structure of 1. The longer distances
around t = 0.8 correspond to sections where the tilting direction switches.
Table 1. Comparison of the structural features of the second subsystem of
1 to neat gold(III) chloride. For AuCl3 all symmetrically independent values
are listed, the value ranges for subsystem II are taken from t-plots.
[a]
AuCl3
Subsystem II of 1
d(Au – Clterm
d(Au –Clbridge
d(Au – Clax
<(Clbridge – Au – Clbridge
<(Clbridge – Au – Clterm
<(Clterm – Au – Clterm
)
2.245(2) Å; 2.251(2) Å
2.333(2) Å; 2.343(2) Å
3.454(2) Å; 3.460(2) Å
85.71(6)°
2.23 Å – 2.27 Å
2.32 Å – 2.38 Å
3.25 Å – 3.26 Å
85° – 87°
)
)
)
)
91.58(6)°; 92.40(6)°
90.31(7)°
90° – 93°
Figure 2. Network built up by subsystem I in the crystal structure of 1.
Structural detail taken at t = 0. The displacement ellipsoids represent
a
)
89° – 92°
probability of 90 %.
[a] We redetermined the crystal structure of AuCl3 based on single crystal
date recorded at 123 K with the lattice constants: a = 6.5316(5),
b = 10.9011(7), c = 6.4072(5) Å and β = 113.477(4)° (see Supporting
Information). The atomic coordinates are in good agreement with those
already published based on room temperature data [6].
The second subsystem consists of planar dinuclear Au2Cl6
molecules, which show almost identical geometric parameters in
comparison to the molecules present in neat AuCl3 [6]. The bond
lengths and angles found for Au2Cl6 in both compounds are very
similar, Table 1 compares their structural features. In the
structure of 1, the dimeric molecules are stacked with their
longer “rectangle edge” next to each other along the channels
built up by the first subsystem. These channels, however, seem
slightly too wide to perfectly house the Au2Cl6 molecules, which
allows the molecules to tilt towards each other (Figures 3 and 4).
Usually, compounds with square-planar coordinated gold(III)
cations show an extended 4+2 or at least 4+1 coordination
sphere for the gold atom. In the crystal structure of 1, this
distorted octahedral coordination is likewise found. Examining
the coordination of the gold atoms of the second subsystem,
contacts to the chlorine atoms of the terminal anions of the first
subsystem are revealed (Figure 5). These contacts range from
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10.1002/zaac.201700455
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3.25 Å to 3.60 Å (Figure 6 top). There are always at least two
contacts below 3.60 Å. In the first half of the modulation (t < 0.5)
the close contacts are present between Au(3) and Cl(2), for the
second half they are present between Au(3) and Cl(1). The
extended coordination sphere for Au(III) around t = 0.5 even
shows up to four additional contacts as close as 3.75 Å, which is
a feature not observed for neat AuCl3.
The closer the contact between the Au2Cl6 dimer and the
chlorine atom, the better is the interaction between the dimer
and the first subsystem. Therefore, fixing of the dimer inside the
channel should be stronger for short contacts. Indeed, this is
reflected by the maximal anisotropic displacement parameters of
the gold atoms shown in bottom of Figure 6. The maximal
displacement is larger for longer contacts and smaller for closer
contacts.
the Au2Cl6 molecules are tilted towards each other to improve
the space filling instead of a uniform arrangement. With the
extended coordination in mind, the tilting may also be interpreted
as an attempt of the Au2Cl6 molecules to optimize their 4+2
coordination interaction with the first subsystem. This is
supported by the fact that the elongation of the displacement
ellipsoids of the Au2Cl6 molecules increases with the length of
the distance between the Au atom and the additional chlorine
ligands, indicating a less tight fixation of the dimers inside the
channel (Figure 6 bottom).
Both independent gold atoms of the first subsystem also exhibit
an extended 4+2 coordination sphere (pink contacts in Figure 5).
The gold atoms of the bridging anions have contacts between
3.30 Å and 3.60 Å to the terminal chlorine atoms of the Au2Cl6
dimers. Finally, the gold atoms of the terminally bound [AuCl4]-
anions fulfill their 4+2 coordination inside their own subsystem,
with contacts from 3.40 Å to 3.60 Å to chlorine atoms of the
symmetrically equivalent ligands belonging to the chains above
and below.
Figure 6. t-Plot of the intersubsystem Au(3)···Cl(1/2) contacts (top) and the
maximal anisotropic displacement parameter (ADP) of Au(3) (bottom) in the
modulated crystal structure of 1. There are always at least two Au···Cl
contacts below 3.60 Å to complete the 4+2 coordination sphere. The ADP
parameter for Au(3) behaves accordingly: for shorter contacts (t = 0.25; 0.75)
the displacement ellipsoid is smaller, while it is higher for longer contacts
(t = 0.0; 0.5).
Supercell approximation of 1: Zn9Au28Cl102
The modulation vector of 1 is close to (2/3; 0; 1/9), which would
open the opportunity for a supercell description as a 27-fold
superstructure. However, refinement as a commensurately
modulated structure yields significantly worse R values. By
omitting part of the diffraction pattern, an acceptable nine-fold
superstructure can be solved and refined in 3D space. All
general features of the modulated structure are present. The
most noticeable error is the exact description of the Au2Cl6
molecules as is evident from their large displacement ellipsoids
(Figure S9). Full data for this approximant is given in the
Supporting Information.
Figure 5. Extended coordination of the gold atoms (depicted as dashed lines)
in the crystal structure of 1 at t = 0. All three independent gold atoms show the
4+2 coordination usually found for gold(III) compounds. The blue and orange
coloured contacts are those depicted in the t-plot in Figure 6. The
displacement ellipsoids represent a probability of 90 %.
With this property in mind the necessity for an incommensurately
modulated composite crystal structure is revealed. The reason
for the intercalated Au2Cl6 dimers lies in the extended
coordination sphere of the gold(III) cations. In the first
subsystem only one of the two independent gold atoms is able
to achieve the 4+2 coordination without the intercalated guest
molecules. A different conformation of the Zn[AuCl4]2 chain
might be sterically hindered by the small size of the zinc(II)
cation. Finally, the translation period of the stacked dimers does
not fit with the translation period of the stacked chains, because
The crystal structure of Cd[AuCl4]2
The compound Cd[AuCl4]2 (2) forms orange-yellow crystals and
crystallizes in the monoclinic space group I2/a (Table 3). The
asymmetric part of the unit cell contains half the formula unit.
The gold atom of the tetrachloridoaurate(III) anion in the first
coordination sphere – as usual for gold(III) – is in an almost
perfect square-planar arrangement. The Au-Cl bond lengths
range between 2.26 Å and 2.32 Å, and the Cl-Au-Cl angles
between 89° and 91° (see Table 2). The coordination around the
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10.1002/zaac.201700455
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cadmium cations, on the other hand, is in form of heavily
distorted octahedra, which is reflected by the wide range of Cl-
Cd-Cl angles from 76° to 101°. The Cd-Cl distances however,
are almost identical between 2.62 Å and 2.63 Å. The six chlorine
atoms belong to four different [AuCl4]– anions, which requires
two anions to act as bidentate ligands. All anions bridge two
adjacent Cd2+ cations, while one cation is always coordinated in
bidentate and the other one in monodentate fashion. This means
in turn, that one chlorine atom of each anion is not part of the
cadmium coordination sphere. The role of this chlorine atom will
be discussed later. The site symmetry requires that pairs of two
anions are co-planar with a Au-Au distance of 4.04 Å. The
bridging anions connect the cations to chains, which run along
the crystallographic c axis (Figure 7).
Figure 8. Extended unit cell of 2 viewed along the crystallographic c axis. The
extended gold coordination sphere is indicated by dashed lines. Displacement
ellipsoids represent a probability of 90 %.
Table 2. Selected distances and angles between atoms in the structure of
2. Superscripts indicate symmetry generated atoms: (i) -x, -½+y, ½-z; (ii) x,
½-y, -½+z; (iii) ½-x, y, -z; (iv) ½-x, ½-y, ½-z.
Atoms
Distance / Å
Atoms
Distance / Å
Au—Cl(1)
Au—Cl(2)
Au—Cl(3)
Au—Cl(4)
Au···Auii
2.261(3)
2.293(1)
2.316(3)
2.286(2)
4.0400(6)
Cd—Cl(2)
Cd—Cl(3)ii
Cd—Cl(4)ii
Au···Cl(1)i
Au···Cl(3)iv
2.623(2)
2.622(2)
2.630(3)
3.338(2)
3.532(2)
Figure 7. Chain running along the crystallographic c axis in the crystal
structure of 2. Displacement ellipsoids represent
a probability of 90 %.
Superscripts indicate symmetry generated atoms: (i) -x, -½+y, ½-z; (ii) x, ½-y, -
½+z; (iii) ½-x, y, -z; (iv) ½-x, ½-y, ½-z.
As was discussed for compound 1, the gold(III) coordination
sphere is usually extended to an elongated octahedron in a 4+2
coordination. In the crystal structure of 2, again two additional
chlorine atoms are present to fulfill the extended coordination.
One of these two atoms is the “non-coordinating” Cl(1)
belonging to an adjacent chain with a Au···Cl distance of 3.33 Å,
the other atom is Cl(3) belonging to a neighboring co-planar
[AuCl4]– anion. Here, the Au···Cl distance is larger and amounts
to 3.53 Å (Figure 8, dashed lines). This extended coordination is
Atoms
Angle / °
Atoms
Angle / °
Cl(1)―Au―Cl(2)
Cl(2)―Au―Cl(3)
Cl(3)―Au―Cl(4)
Cl(4)―Au―Cl(1)
Cl(3)ii―Cd―Cl(3)iv
Cl(3)iv―Cd―Cl(4)ii
Cl(3)ii―Cd―Cl(4)ii
90.30(7)
89.87(7)
89.60(7)
90.24(7)
99.29(9)
94.97(6)
76.26(6)
Cl(2)―Cd―Cl(2)iii
Cl(2)―Cd―Cl(3)iv
Cl(2)―Cd―Cl(4)ii
Cl(2)―Cd―Cl(4)iv
Cl(1)···Au···Cl(1)i
Cl(1)···Au···Cl(3)iv
77.64(8)
93.28(6)
90.11(6)
100.36(6)
101.44(7)
82.17(7)
reflected
by
the
Au-Cl
distances
within
the
tetrachloridoaurate(III) anions. The shortest Au-Cl bond is
present for the chlorine atom, which is not part of the cadmium
coordination sphere, while the longest Au-Cl bond is found for
the chlorine atom, which is part of the extended 4+2 coordination
of an adjacent gold atom.
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Table 3. Crystallographic data and details of the structure refinement for
Zn[AuCl4]2·(AuCl3)1.115 (1) and Cd[AuCl4]2 (2). Standard deviations given in
brackets refer to the last significant digit.
Table 4. Additional crystallographic data for Zn[AuCl4]2·(AuCl3)1.115 (1).
Compound
Zn[AuCl4]2·(AuCl3)1.115 (1)
Cd[AuCl4]2 (2)
Subsystem I
Subsystem II
Mr / g·mol-1
1081.12
789.93
[1 0 0 0;
0 1 0 0;
0 0 1 0;
0 0 0 1]
[1 0 0 0;
0 1 0 0;
0 0 1 1;
0 0 1 1]
Composite matrix Wν
Temperature / K
Crystal system
Space group
123(2)
Monoclinic
I2/a (No. 15)
Space group
C2/c(α0γ)0s
C2/m(α0γ)0s
C2/c(α0γ)0s
a = 9.2485 Å
b = 23.7995 Å
c = 7.5926 Å
β = 93.405°
q = (0.6600; 0;
0.1143)
a = 10.5213 Å
b = 23.7995 Å
c = 6.8136 Å
β = 118.661°
q = (-0.5923; 0;
0.8974)
Lattice constants
a = 9.248(3) Å
b = 23.799(7) Å
c = 7.593(2) Å
β = 93.41(1)°
q = (0.6600(4); 0; 0.1143(4))
a = 12.2612(7) Å
b = 7.3511(4) Å
c = 12.8244(8) Å
β = 95.403(5)°
Lattice constants
Volume / ų
Z
1668.3(9)
4
1150.8(2)
4
Volume / ų
Contents
Z
1668.3
Zn[AuCl4]2
4
1497.1
½ Au2Cl6
4
Calc. density / g cm-3
Radiation
4.304
4.559
Mo-Kα radiation λ = 0.71073 Å
4 positional and 2 ADP modulation waves for each atom
Crystal size / µm³
Theta range
Completeness
Limiting indices
86  70  46
88  58  2
0.92 ° ≤ θ ≤ 47.43°
98 % for θ = 26.62°
3.2° ≤ θ ≤ 27.5°
100 % for θ = 25.24°
|h| ≤ 17; |k| ≤ 37;
|l| ≤ 12; |m| ≤ 4
|h| ≤ 21; |k| ≤ 9;
|l| ≤ 15
Conclusions
Reflections. collected /
unique
117367 / 29752
9785 / 1319
Two salt-like compounds of dications with [AuCl4]− anions were
synthesized. The use of liquid chlorine as solvent was crucial to
obtain crystalline products. The single crystal structures of
Zn[AuCl4]2·(AuCl3)1.115 (1) and Cd[AuCl4]2 (2) exhibit an extended
4+2 coordination sphere around the Au(III) cation. In the
structure of 2 this elongated octahedral coordination is achieved
by building chains which are arranged in a pseudo-hexagonal
rod packing. In the structure of 1, Au2Cl6 molecules are
intercalated as guest molecules into its honeycomb-like network
to complete the gold coordination sphere. The resulting intricate
crystal structure is best described as an incommensurately
modulated two-sublattices composite structure.
Absorption correction /
Abs. coefficient / mm-1
SADABS /
30.502
MULTISCAN /
29.060
Max. / min
transmission
0.4357 / 0.2649
433 / F
0.1822 / 0.0802
51 / F2
Refined parameters /
against
R1; wR2 (all data) [a]
R1; wR2 (obs) [a]
0.1721; wR = 0.0631
0.0375; 0.0569
0.0555; wR = 0.0576
n(I > 3σ) = 11923
0.0270; 0.0545
n(I > 4σ) = 1112
R1 main / 1st / 2nd
R1 3rd / 4th (obs)
3.46 % / 5.66 % / 7.98 %
14.09 % / 21.19 %
―
Experimental Section
Goodness-of-Fit
1.57
1.092
Zn[AuCl4]2∙(AuCl3)1.115 (1): Gold powder, precipitated by reduction with
gaseous SO2 from HAuCl4 solution (104 mg, 0.53 mmol) and ZnCl2,
prepared from elemental zinc and hydrogen chloride at 700 °C (21.1 mg,
0.16 mml) were charged in a borosilicate ampoule (~10 cm length,
12.9 mm diameter, 2.2 mm wall thickness). Chlorine (Praxair, Düsseldorf,
99.9 %), was condensed onto the mixture (filling level 25 %). The
chlorine was frozen with liquid nitrogen and the ampoule was sealed
under reduced pressure and placed vertically for four weeks at ambient
temperature. The ampoule was opened, the excess of chlorine
evaporated and the orange powder was sealed under reduced pressure
in a glass ampoule (length 20 cm) having an additional constriction. The
Largest peak /
hole / e- Å-³
+14.44 / -16.48 (3+1D)
integr. charge: +2.23 /
-3.47
+1.329 / -1.731
−1
2
[a] Weighting scheme for 1: 푤 = [휎2퐹 + 0.0001퐹
and for 2: 푤 = 1/[휎2퐹
]
표
표
1
2
(
)
+
0.0083푃 2 + 7.7789푃2] with 푃 = (퐹 2 + 2퐹 2
)
푐
표
표
3
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10.1002/zaac.201700455
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ampoule was placed asymmetrically in the temperature gradient of a tube
furnace for one week at 230 °C to sublimate off the excess of gold(III)
chloride into the colder part. The constriction was sealed to separate
AuCl3 and 1, which remains in the warmer part. Longer reaction times for
the first step improved yield and crystallinity.
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P. Gütlich, B. Lehnis, K. Römhild, J. Strähle, Z. Naturforsch. B 1982, 37,
550-556; n) E. Schulz Lang, U. Abram, J. Strähle, Z. Anorg. Allg. Chem.
1997, 623, 1791-1795.
Cd[AuCl4]2 (2): The synthetic procedure follows the protocol described
for the synthesis of 1. Gold powder (58.8 mg, 0.30 mmol) and CdCl2
(27.4 mg, 0.15 mmol), synthesized from elemental cadmium and
hydrogen chloride at 450 °C, were used.
Crystal Structure Determinations: Crystals of 1 and 2 suitable for X-ray
analysis were selected in perfluorinated polyether (FOMBLIN Y HVAC
140/13, Solvay, Brussels, BE) and transferred to a Bruker Nonius
kappaCCD diffractometer equipped with graphite-monochromatized Mo-
Kα radiation and an Oxford Cryostream 700 crystal cooling device. Cell
determination and data collection were carried out at 123 K. The data
collection was performed by COLLECT [7]. Data integration for 1 was
[2]
a) B. G. Müller, Z Anorg. Allg. Chem. 1987, 555, 57-63; b) H. Bialowons,
B. G. Müller, Z Anorg. Allg. Chem. 1997, 623, 434-438; c) R. Fischer, B.
G. Müller, Z Anorg. Allg. Chem. 1997, 623, 1729-1733; d) R. Schmidt,
B. G. Müller, Z Anorg. Allg. Chem. 1999, 625, 605-608; e) H. Bialowons,
B. G. Müller, Z Anorg. Allg. Chem. 1997, 623, 1719-1722.
P. G. Jones, R. Schelbach, E. Schwarzmann, C. Thöne, Acta Cryst. C
1988, 44, 1162-1164.
performed by APEX2 [8], followed by
a semi-empirical absorption
correction as implemented in SADABS [8]. The initial, modulated
structure solution was achieved by charge flipping as implemented by
SUPERFLIP [9], interpretation of the resulting electron density and
further structure refinement was done with JANA2006 [10]. Diamond [11]
was used for structure visualisation.
[3]
[4]
P. E. Plyusnin, I. A. Baidina, Y. V. Shubin, S. V. Korenev, Russ. J. Inorg.
Chem. 2007, 52, 371-377.
[5]
[6]
O. Graudejus, B. G. Müller, Z. Anorg. Allg. Chem. 1996, 622, 187-190.
a) E. S. Clark, D. H. Templeton, C. H. MacGillavry, Acta Cryst 1958, 11,
284–88; b) P. Schwerdtfeger, P. D. W. Boyd, S. Brienne, A. K. Burrell,
Inorg. Chem. 1992, 31, 3411-3422.
Data integration for 2 was done using DENZO [12], followed by a semi-
empirical absorption correction suitable for area detectors as proposed
by Blessing [13] (implemented in PLATON [14]). The structure was
solved by charge flipping using SUPERFLIP and refined with anisotropic
displacement parameters for all atoms with SHELXL 2014 [15]. The
setting I2/a was chosen to avoid an extreme monoclinic angle in the
standard setting C2/c (lattice constants of the C2/c cell: a = 16.8876(10),
b = 7.3511(4), c = 12.2612(7) Å, β = 130.885(2)°).
[7]
[8]
COLLECT, Nonius BV, Delft, 1999.
APEX2, SAINT und SADABS, Bruker AXS Inc., Madison, Wisconsin,
USA, 2004.
[9]
L. Palatinus, G. Chapuis, J. Appl. Crystallogr. 2007, 40, 786-790.
[10] V. Petrícek, M. Dušek, L. Palatinus, Z. Kristallogr. 2014, 229, 345-352.
[11] K. Brandenburg, Diamond 3.2k, Crystal Impact GbR, Bonn, 2014.
[12] Z. Otwinowski, W. Minor, J. Charles W. Carter, in Macromolecular
Crystallography Part A, Bd. 276, Academic Press, 1997, 307-326.
[13] R. H. Blessing, Acta Cryst. A 1995, 51, 33-38.
Further details of the crystal structure investigations may be obtained
from the Fachinformationszentrum Karlsruhe, 76344 Eggenstein-
Leopoldshafen, Germany, E-mail: crysdata@fiz-karlsruhe.de, on quoting
the CSD number CSD-433230 for Cd[AuCl4]2 (2) and CSD-433229 for
AuCl3 (123 K). Modulated data for Zn[AuCl4]2∙(AuCl3)1.115 (1) have been
deposited under the CSD number CSD-433327, the commensurate
approximant Zn9Au28Cl102 is available under CSD-433231.
[14] a) A. L. Spek, J. Appl. Crystallogr. 2003, 36, 7-13; b) A. L. Spek, Acta
Cryst. D 2009, 65, 148-155.
[15] G. M. Sheldrick, Acta Cryst. A 2008, 64, 112-122.
Supporting Information
Supporting Information is available for this article (15 pages): DSC data,
diffraction images, additional t-plots and positional parameters of 1,
positional parameters and thermal displacement parameters of 2,
complete crystallographic data of the structure of AuCl3 at 123 K,
crystallographic data of the supercell approximation of 1.
Acknowledgements
We thank Sven Lidin for helpful discussions and Ralf Weisbarth
for DSC investigations.
Keywords: Tetrachloridoaurate • Zinc • Cadmium •
Incommensurate structure • Composite crystal
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10.1002/zaac.201700455
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The first salt-like compounds of
divalent metal cations with [AuCl4]−
anions are reported. The compounds
Christian Landvogt, Johannes Beck*
Page No. – Page No.
Zn[AuCl4]2·(AuCl3)1.115
(1)
and
The Tetrachloridoaurates(III) of Zn(II)
and Cd(II)
Cd[AuCl4]2 (2) are obtained from
reactions of MCl2 (M = Zn, Cd) and
elemental gold in liquid chlorine. 1 is
an
incommensurately
modulated
composite built of polymeric zinc(II)
tetrachloridoaurate(III) and embedded
Au2Cl6 molecules. 2 consists of chains of
Cd2+ ions bridged by [AuCl4]– anions.
Both M2+ cations posses a distorted
octahedral coordination environment.
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10.1002/zaac.201700455
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