Three-Dimensional Polymeric Thallium(I) Morpholinedithiocarbamate [Tl2{S2CN(CH2)4O}2]n and Its Capability of Binding Gold(III) from Solutions: Chemisorption Synthesis of a Heteronuclear Gold(III)–Thallium(III) Complex of the Ionic Type, ([Au{S2CN(CH2)4O}2][TlCl4])n, the Role of Secondary Interactions Tl…O, Tl…S, and Au…S in the Supramolecular Self-Organization, 13C MAS NMR, and Thermal Behavior

Article abstract of DOI:10.1134/S1070328417100013

Crystalline polymeric thallium(I) morpholinedithiocarbamate [Tl₂{S₂CN(CH₂)₄O}₂]_n (I) and the heteronuclear ion–polymeric gold(III)–thalium(III) complex ([Au{S₂CN(CH₂)₄O}₂][TlCl₄])_n (II) are preparatively isolated and characterized by X-ray diffraction analysis and ¹³C MAS NMR spectroscopy. According to the X-ray diffraction data, the main structural units of compounds I and II (CIF files CCDC 1548079 and 1548080) are presented by the binuclear centrosymmetric molecule [Tl₂{S₂CN(CH₂)₄O}₂], noncentrosymmetric complex cation [Au{S₂CN(CH₂)₄O{₂]⁺, and isomeric complex anions [TlCl₄]^–. The formation of the three-dimensional polymeric structure (coordination number of Tl is 7), which is not characteristic of thallium(I) dithiocarbamates, is a consequence of the participation of the secondary Tl…O and Tl…S bonds of two types in the supramolecular self-organization of compound I. Nonequivalent secondary interactions of the first type join the binuclear molecules [Tl₂{S₂CN(CH₂)₄O}₂] into polymer layers, which, in turn, form the three-dimensional polymeric framework due to the secondary bonds Tl…S. The revealed ability of freshly precipitated compound I to the chemisorption of gold(III) from solutions (2 M HCl) makes it possible to obtain heteronuclear supramolecular complex II as an individual form of binding. In the structure of the latter, the pairs of stronger secondary Au…S bonds join the gold(III) cations into dimers [Au₂{S₂CN(CH₂)₄O}₄]²⁺ of the angular structure, the structural ordering of which is achieved in the cationcationic polymeric chain ([Au₂{S₂CN(CH₂)₄O}₄]²⁺)_n of the helical type involving the pairs of less strong Au…S bonds between the adjacent binuclear units. The distorted tetrahedral anions [TlCl₄]^– are localized between the polymeric chains. The study of the thermal behavior of compounds I and II by simultaneous thermal analysis makes it possible to establish the character of thermal transformations of the substances and to identify Tl₂S (I), TlCl, and elemental gold (II) as thermolysis products.

Full text of DOI:10.1134/S1070328417100013

ISSN 1070-3284, Russian Journal of Coordination Chemistry, 2017, Vol. 43, No. 10, pp. 638–651. © Pleiades Publishing, Ltd., 2017.
Original Russian Text © O.A. Bredyuk, O.V. Loseva, A.V. Ivanov, V. Gowda, O.N. Antzutkin, 2017, published in Koordinatsionnaya Khimiya, 2017, Vol. 43, No. 10, pp. 602–
616.
Three-Dimensional Polymeric Thallium(I)
Morpholinedithiocarbamate [Tl2{S2CN(CH2)4O}2]n
and Its Capability of Binding Gold(III)
from Solutions: Chemisorption Synthesis of a Heteronuclear
Gold(III)–Thallium(III) Complex of the Ionic Type,
([Au{S2CN(CH2)4O}2][TlCl4])n, the Role of Secondary Interactions
Tl⋅⋅⋅O, Tl⋅⋅⋅S, and Au⋅⋅⋅S in the Supramolecular Self-Organization,
13C MAS NMR, and Thermal Behavior
O. A. Bredyuka, O. V. Losevaa, A. V. Ivanova, *, V. Gowdab, c, and O. N. Antzutkinb, d
a Institute of Geology and Nature Management, Far East Branch, Russian Academy of Sciences, Relochnyi per. 1,
Blagoveshchensk, 675000 Russia
b Luleå University of Technology, SE-97187 Luleå, Sweden
c University of Oulu, P.O. Box 3000, FI-90014 Oulu, Finland
d Warwick University, Coventry CV4 7AL, UK
*e-mail: alexander.v.ivanov@chemist.com
Received May 8, 2017
Abstract—Crystalline polymeric thallium(I) morpholinedithiocarbamate [Tl2{S2CN(CH2)4O}2]n (I) and the
heteronuclear ion–polymeric gold(III)–thalium(III) complex ([Au{S2CN(CH2)4O}2][TlCl4])n (II) are pre-
paratively isolated and characterized by X-ray diffraction analysis and 13C MAS NMR spectroscopy. Accord-
ing to the X-ray diffraction data, the main structural units of compounds I and II (CIF files CCDC 1548079
and 1548080) are presented by the binuclear centrosymmetric molecule [Tl2{S2CN(CH2)4O}2], noncen-
trosymmetric complex cation [Au{S2CN(CH2)4O}2]+, and isomeric complex anions [TlCl4]–. The formation
of the three-dimensional polymeric structure (coordination number of Tl is 7), which is not characteristic of
thallium(I) dithiocarbamates, is a consequence of the participation of the secondary Tl⋅⋅⋅O and Tl⋅⋅⋅S bonds
of two types in the supramolecular self-organization of compound I. Nonequivalent secondary interactions
of the first type join the binuclear molecules [Tl2{S2CN(CH2)4O}2] into polymer layers, which, in turn, form
the three-dimensional polymeric framework due to the secondary bonds Tl⋅⋅⋅S. The revealed ability of freshly
precipitated compound I to the chemisorption of gold(III) from solutions (2 M HCl) makes it possible to
obtain heteronuclear supramolecular complex II as an individual form of binding. In the structure of the lat-
ter, the pairs of stronger secondary Au⋅⋅⋅S bonds join the gold(III) cations into dimers
[Au2{S2CN(CH2)4O}4]2+ of the angular structure, the structural ordering of which is achieved in the cation-
cationic polymeric chain ([Au2{S2CN(CH2)4O}4]2+)n of the helical type involving the pairs of less strong
Au⋅⋅⋅S bonds between the adjacent binuclear units. The distorted tetrahedral anions [TlCl4]– are localized
between the polymeric chains. The study of the thermal behavior of compounds I and II by simultaneous
thermal analysis makes it possible to establish the character of thermal transformations of the substances and
to identify Tl2S (I), TlCl, and elemental gold (II) as thermolysis products.
Keywords: three-dimensional polymeric thallium(I) alkylenedithiocarbamates, chemisorption binding of
gold from solutions, heteronuclear gold(III)–thallium(III) dithiocarbamato-chlorido complexes, secondary
interactions and self-organization of supramolecular structures, X-ray diffraction analysis, 13С MAS NMR,
simultaneous thermal analysis
DOI: 10.1134/S1070328417100013
INTRODUCTION
lysts, dyes, and pigments, as well as in nuclear medi-
cine [1, 2]. Interest in thallium dithiocarbamates is
Thallium and its compounds are applied in various
areas of practical activity: as semiconductors, cata- evoked by their unusually complicated supramolecular
638

THREE-DIMENSIONAL POLYMERIC THALLIUM(I) MORPHOLINEDITHIOCARBAMATE
639
structures stabilized by secondary interactions of dif- Synthesis of compound I was carried out by the
ferent types [3–9] and by the possibility of practical reaction of a solution of TlNO3 (Merck) (0.0727 g,
use as precursors of various film and nanosized thal-
lium sulfides [10–17]. An enhanced reactivity of
highly dispersed thallium dithiocarbamates caused by
a significant total concentration of coordinately unsat-
urated centers of sulfur and thallium in the developed
surface layer indicates the possibility of their use as
efficient chemisorbents of metal ions from solutions.
0.2729 mmol) in water (10 mL) with a solution of
Na{S2CN(CH2)4O} ⋅ 2H2O (0.0604 g, 0.2729 mmol)
in water (10 mL). The white bulky precipitate was fil-
tered off, washed with water, and dried in air. The yield
was 78%. To obtain single crystals, the complex was
dissolved in boiling N,N-dimethylformamide
(∼153°C). Colorless transparent crystals were formed
immediately on cooling the solution. For further
experiments, cubic crystals of compound I were taken
from the mother liquor and dried on a filter.
The chemisorption synthesis of compound II was
based on binding AuCl3 from a solution in 2 M HCl
with freshly precipitated thallium(I) morpholinedith-
iocarbamate [Tl2{S2CN(CH2)4O}2]n, being a bulky
microcrystalline white precipitate. The interaction of
the precipitate with a solution of H[AuCl4] results in a
change in the color to yellow already at the first min-
utes with the simultaneous decoloration of the work-
ing solution. The degree of binding gold from the solu-
tion to the solid phase (98.3%) indicates the formation
of new compounds in the studied system. The hetero-
geneous reaction of gold(III) binding to the solid
phase includes the partial ion exchange and redox pro-
cess:
Polynuclear thallium(I) N,N-cyclo-pentamethylene-
[18, 19] and N,N-cyclo-hexamethylenedithiocarbamates
[20] studied by us earlier are characterized by two-
dimensional polymeric supramolecular structures in the
formation of which the secondary Tl⋅⋅⋅S bonds play the
determining role. The study of the chemisorption activity
of thallium(I) dialkyldithiocarbamates [Tl2(S2CNR2)2]n
(R = СH3, С2H5, iso-C4H9) including linear and
branched substituents toward solutions of gold(III) in
2 M HCl made it possible to obtain and characterize in
detail ion–polymeric heteronuclear gold(III)–thal-
lium(III) complexes [Au2{S2CN(CH3)2}4][TlCl4]2 and
([Au(S2CNR2)2][TlCl4])n (R = C2H5, iso-С4H9) [21, 22].
Therefore, it seemed interesting to study the ability of
thallium(I) morpholinedithiocarbamate (MfDtc),
whose ligand contains the heterocyclic fragment, to bind
gold(III) from solutions.
3[Tl2{S2CN(СН2)4O}2] + 5H[AuCl4]
= 3[Au{S2CN(СH2)4O}2][TlCl4]
+ 3TlCl + 2Au + 5HCl.
Polymeric bis[μ2-(morpholinedithiocarbamato-
S,S,S',S')]dithallium(I) [Tl2{S2CN(CH2)4O}2]n (I),
the first representative of thallium(I) dithiocarbamate
complexes with the three-dimensional polymeric
structure, was obtained in this work. The role of the
secondary Tl⋅⋅⋅O and Tl⋅⋅⋅S interactions in the supra-
molecular self-organization of compound I was
shown, and its reactivity toward [AuCl4]–/2 M HCl
was studied. The formation of ion–polymeric
bis(morpholinedithiocarbamato-S,S')gold(III) tetra-
chlorothallate(III) ([Au{S2CN(CH2)4O}2][TlCl4])n
(II) was established by the results of the chemisorption
binding of gold(III) and the accompanying redox pro-
cess. The supramolecular structures of preparatively
isolated crystalline compounds I and II were charac-
terized in detail by the X-ray diffraction and 13С MAS
NMR data. The thermal behavior and conditions for
the regeneration of bound gold(III) were studied by
simultaneous thermal analysis (STA).
A solution of AuCl3 (10 mL) in 2М hydrochloric
acid containing 44.5 mg of gold was poured to com-
plex I (100 mg), and the mixture was stirred for 1 h.
The residual content of gold in the solution was deter-
mined on a Hitachi atomic absorption spectrometer
(1 class, model 180-50). The obtained yellow precipi-
tate was filtered off, washed with water, dried on a fil-
ter, and dissolved in acetone on heating. Transparent
crystals of compound II (yellow needles) for diffrac-
tion analysis were obtained by the slow evaporation of
the solvent at room temperature.
13C MAS NMR data (δ, ppm) for [Tl2-
{S2CN(CH2)4O}2]n (I): 205.2 (=NC(S)S–); 67.2
(‒OCH2–); 51.0, 49.7 (1 : 1, =NCH2–); for
([Au{S2CN(CH2)4O}2][TlCl4])n (II): 198.6, 194.3
(1 : 1, =NC(S)S–); 67.0, 66.0, 65.0 (2 : 1 : 1, –OCH2–);
51.4, 49.2, 48.7 (2 : 1 : 1, =NCH2–).
13C MAS NMR spectra were recorded on an
Ascend Aeon spectrometer (Bruker) with a working
frequency of 100.64 MHz (for 13C), a superconducting
magnet (В0 = 9.4 T) with the closed condensation
cycle of helium through an external compressor, and
the Fourier transform. Proton cross polarization and
the decoupling effect for the suppression of 13C−1H
interactions using a radiofrequency field at the reso-
nance frequency of protons were applied [24]. Sam-
ples of complexes I and II (~50 or 80 mg, respectively)
EXPERIMENTAL
Sodium morpholinedithiocarbamate was obtained
by the reaction of carbon bisulfide (Merck) and mor-
pholine (Aldrich) in an alkaline medium [23]. The
starting salt was additionally characterized by the
13С MAS NMR spectroscopy:
for Na{S2CN(CH2)4O} ⋅ 2H2O (δ, ppm):
204.8 (=NC(S)S–); 67.6, 67.2 (–OCH2–); 54.6, 53.9,
53.5 (=NCH2–).
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 43 No. 10 2017

640
BREDYUK et al.
were placed in a 4.0-mm ceramic rotor of ZrO2. The independently with a PTP(M) instrument (OAO
Khimlaborpribor, Russia).
RESULTS AND DISCUSSION
rotation of a sample at the magic angle and a fre-
quency of 10 000(1) Hz was used in 13C MAS NMR
measurements and 10240 or 1320 signal transients
were accumulated, with a duration of proton π/2
pulses of 2.7 μs, a contact time 1H−13C of 3.0 ms, and
a pulse delay of 5.0 or 3.0 s. Isotropic chemical shifts
(δ(13C), ppm) are given relative to one of the compo-
nents of crystalline adamantane used as an external
standard (δ = 38.48 ppm relative to tetramethylsilane)
with a correction applied to the drift of the magnetic
The 13С MAS NMR spectra of complexes I and II
contain resonance signals of the =NC(S)S–,
‒ОCH2–, and =NCH2– groups (Fig. 1). The dithio-
carbamate groups most sensitive to the structural state
of the MfDtc ligands are presented in the experimental
field strength, whose frequency equivalent was spectra by one or two (1 : 1) 13С resonance signals. It is
0.025 Hz/h.
X-ray diffraction analysis. Single crystals of com-
clear from this that in compound I the ligands are
structurally unified, whereas the structure of com-
pound II contains two groups of nonequivalent MfDtc
ligands. Note that heteronuclear complex II is charac-
terized by significantly lower (compared to the starting
polymeric complex I) 13С chemical shifts of the
=NC(S)S– groups (see the syntheses of compounds I
and II). The revealed decrease (by 6.6 and 10.9 ppm)
in the discussed values of δ(13С) indicates the com-
plete redistribution of the MfDtc ligands in the inter-
nal sphere of gold(III), whose electron density is
involved more efficiently in the additional shielding of
the carbon rings of the dithiocarbamate groups. In the
small-sized four-membered rings [AuS2C], the posi-
tions of the oppositely lying gold and carbon atoms are
pounds I and II were fixed at the end of a glass capil-
lary with the epoxide resin. Experiments were carried
out on a Bruker-Nonius X8 Apex CCD diffractometer
(MoKα radiation, λ = 0.71073 Å, graphite monochro-
mator) at 150(2) K. The data were collected using a
standard procedure: ϕ and ω scanning of narrow
frames. An absorption correction was applied empiri-
cally using the SADABS program [25]. The structures
were determined by a direct method and refined by
least squares (for F2) in the full-matrix anisotropic
approximation of non-hydrogen atoms. The positions
of hydrogen atoms were calculated geometrically and
included into the refinement by the riding model. The
calculations on structure determination and refine- substantially approached, indicating trans-annular
ment were performed using the SHELXTL program interactions between them.
package [25]. The main crystallographic data and
The structural organization of the synthesized
complexes was established by X-ray diffraction analysis.
Before discussing the structures of compounds I/II, let
us consider the general features of the MfDtc ligands.
The N–C(S)S bonds are shorter (1.344/1.309,
1.293 Å) than those of N–CH2 (1.462, 1.468/1.45–
1.490 Å), which indicates a considerable contribution
of double bonding to the formally ordinary bond (and
admixing of the sp2-hybrid state to the sp3-hybrid state
of the nitrogen and carbon atoms) due to the meso-
meric effect of the =NC(S)S– groups. Not quite
coplanar (due to the peripheral carbon atoms) mutual
arrangement of atoms in the structural C2NCS2
groups is illustrated by the torsion angles S–C–N–C,
the deviation of which from 0° or 180° does not exceed
6.3° and 7.9°, respectively (Table 2). The six-mem-
bered heterocyclic –N(CH2)4O fragments in the chair
conformation are trans-oriented relative to the equa-
torial plane of the octahedral molecule
[Tl2{S2CN(CH2)4O}2]. On the contrary, in the com-
results of structure refinement are presented in
Table 1. Selected bond lengths and angles are given in
Table 2.
The coordinates of atoms, bond lengths, and angles
were deposited with the Cambridge Crystallographic
Data Centre (CIF files CCDC 1548079 (I) and 1548080
(II); deposit@ccdc.cam.ac.uk or http://www.ccdc.
cam.ac.uk).
Thermal behavior of compounds I and II was stud-
ied by the STA method with the simultaneous detec-
tion of thermogravimetry (TG) and differential scan-
ning calorimetry (DSC) curves. The study was carried
out on an STA 449C Jupiter instrument (NETZSCH)
in corundum crucibles under caps with a hole provid-
ing a vapor pressure of 1 atm in the course of the ther-
mal decomposition of the sample. The heating rate
was 5°C/min to 455 and 1100°C in an argon atmo-
sphere. The limiting heating temperature for com-
pound I was chosen by the fact that Tl2S melts at 449
or 452°C (depending on the method of preparation)
[26]. The weight of the samples was 3.466–9.594 (I)
and 2.787–10.511 mg (II), the accuracy of tempera-
ture measurements was 0.4°C, and the weight
change was 1 × 10−4 mg. When recording TG and
DSC curves, the correction file was used, as well as
calibrations by temperature and sensitivity for a speci-
plex cations [Au{S2CN(CH2)4O}2]+, the discussed
cyclic groups exist in the cis-position relative to the
plane of the [AuS4] chromophore. The bond angles in
the heterocycles of the MfDtc ligands in the com-
plexes I and II mainly exceed the ideal tetrahedral
value and range from 109.5° to 112.8° and from 108.9°
fied temperature program and heating rate. The melt- to 119.7°, and the C–O bond lengths are 1.1.427(6),
ing points of compounds I and II were determined 1.432(7)/1.390(9)–1.436(11) Å, respectively.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY
Vol. 43
No. 10
2017

THREE-DIMENSIONAL POLYMERIC THALLIUM(I) MORPHOLINEDITHIOCARBAMATE
641
Table 1. Crystallographic data and experimental and refinement parameters for the structures of compounds
[Tl2{S2CN(CH2)4O}2]n (I) and ([Au{S2CN(CH2)4O}2][TlCl4])n (II)
Value
Parameter
I
II
Empirical formula
FW
C10H16N2O2S4Tl2
733.23
C10H16N2O2S4Cl4AuTl
867.62
Crystal system
Space group
a, Å
Triclinic
P1
Orthorhombic
Pnna
6.5260(8)
8.4243(7)
8.8900(8)
66.529(4)
83.685(5)
67.550(4)
413.82(7)
15.3384(10)
13.2260(6)
b, Å
c, Å
21.8178(14)
α, deg
β, deg
γ, deg
V, Å3
4426.1(5)
Z
1
8
calcd, g/cm3
2.942
2.604
ρ
μ, mm–1
19.950
14.761
F(000)
332
3184
Crystal size, mm
0.12 × 0.10 × 0.05
2.84–27.50
0.30 × 0.04 × 0.04
1.80–27.53
Range of data collection over θ, deg
Ranges of reflection indices
–8 ≤ h ≤ 5,
–10 ≤ k ≤ 10,
–11 ≤ l ≤ 11
–19 ≤ h ≤ 14,
–15 ≤ k ≤ 17,
–28 ≤ l ≤ 24
Measured reflections
Independent reflections
Reflections with I > 2σ(I)
Refinement variables
GООF
3314
15 955
1880 (Rint = 0.0308)
5098 (Rint = 0.0646)
1748
91
3164
245
1.039
0.999
R factors for F2 > 2σ(F2)
R1 = 0.0264,
wR2 = 0.0570
R1 = 0.0488,
wR2 = 0.1010
R factors for all reflections
R1 = 0.0296,
wR2 = 0.0579
R1 = 0.0997,
wR2 = 0.1128
Residual electron density (min/max), e/Å3
–1.483/1.196
–2.231/1.973
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 43 No. 10 2017

642
BREDYUK et al.
Table 2. Selected bond lengths (d), bond angles (ω), and torsion angles (ϕ) in compounds I and II*
I
Bond
d, Å
Bond
Tl(1)···O(1)d
d, Å
Tl(1)–S(1)
Tl(1)–S(1)a
Tl(1)–S(2)
Tl(1)–S(2)a
Tl(1)···S(2)b
Tl(1)···O(1)c
3.0148(13)
3.1042(14)
3.3472(15)
3.0775(13)
3.6873(15)
3.175(4)
3.112(4)
1.729(6)
1.716(5)
1.344(6)
1.468(6)
1.462(6)
S(1)–C(1)
S(2)–C(1)
N(1)–C(1)
N(1)–C(2)
N(1)–C(4)
Angle
ω, deg
Angle
ω, deg
O(1)cTl(1)S(2)b
O(1)dTl(1)S(1)
O(1)dTl(1)S(2)
O(1)dTl(1)S(1)a
O(1)dTl(1)S(2)a
O(1)dTl(1)S(2)b
O(1)cTl(1)O(1)d
Tl(1)S(1)C(1)
S(1)Tl(1)S(2)
55.30(3)
104.47(3)
83.78(3)
81.07(3)
78.09(3)
108.77(3)
136.11(4)
57.36(4)
122.05(3)
66.38(4)
100.78(7)
89.76(7)
138.00(7)
159.61(8)
ϕ, deg
94.50(7)
161.23(8)
143.36(7)
85.68(8)
88.78(7)
80.17(7)
80.65(10)
91.59(17)
81.08(18)
84.31(17)
85.36(17)
75.52(3)
71.23(3)
119.0(3)
ϕ, deg
S(1)Tl(1)S(1)a
S(1)Tl(1)S(2)a
S(1)Tl(1)S(2)b
S(2)Tl(1)S(1)a
S(2)Tl(1)S(2)a
S(2)Tl(1)S(2)b
S(1)aTl(1)S(2)a
S(1)aTl(1)S(2)b
S(2)aTl(1)S(2)b
O(1)cTl(1)S(1)
O(1)cTl(1)S(2)
O(1)cTl(1)S(1)a
O(1)cTl(1)S(2)a
Tl(1)S(2)C(1)
Tl(1)aS(1)C(1)
Tl(1)aS(2)C(1)
Tl(1)S(1)Tl(1)a
Tl(1)S(2)Tl(1)a
S(1)C(1)S(2)
Angle
Angle
138.3(4)
–136.5(4)
144.9(3)
–6.3(7)
–176.3(4)
174.1(4)
4.1(7)
Tl(1)S(1)S(2)C(1)
Tl(1)aS(1)S(2)C(1)
S(1)C(1)N(1)C(2)
S(1)C(1)N(1)C(4)
S(1)Tl(1)C(1)S(2)
S(2)C(1)N(1)C(2)
S(2)C(1)N(1)C(4)
S(1)Tl(1)aC(1)S(2)
Bond
–144.2(3)
II
d, Å
Bond
d, Å
Cation
S(3)–C(6)
2.331(3)
2.337(3)
2.332(3)
2.330(3)
3.576(3)
1.742(10)
1.711(11)
1.293(14)
1.45(2)
Au(1)–S(1)
Au(1)–S(2)
Au(1)–S(3)
Au(1)–S(4)
S(4)–C(6)
N(1)–C(1)
N(1)–C(2)
N(1)–C(5)
Au(1)···S(2)а
1.49(2)
Au(1)···S(4)b
S(1)–C(1)
S(2)–C(1)
N(2)–C(6)
3.559(3)
1.718(12)
1.725(12)
1.309(12)
1.490(13)
1.474(12)
N(2)–C(7)
N(2)–C(10)
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY
Vol. 43
No. 10
2017

THREE-DIMENSIONAL POLYMERIC THALLIUM(I) MORPHOLINEDITHIOCARBAMATE
Table 2. (Contd.)
643
Anions
Tl(1)–Cl(2)
Tl(1)–Cl(1)
Tl(2A)–Cl(3)
2.418(2)
2.447(4)
2.390(8)
2.302(5)
2.443(3)
2.371(5)
2.46(2)
2.49(2)
Tl(2B)–Cl(3)d
Tl(2B)–Cl(5)
Tl(2B)–Cl(6)
Tl(2A)–Cl(4)
Tl(2B)–Cl(3)
Angle
ω, deg
Angle
ω, deg
Cation
S(1)Au(1)S(2)
S(1)Au(1)S(3)
S(1)Au(1)S(4)
S(2)Au(1)S(3)
S(2)Au(1)S(4)
S(3)Au(1)S(4)
Au(1)S(1)C(1)
Au(1)S(2)C(1)
Au(1)S(3)C(6)
Au(1)S(4)C(6)
S(1)C(1)S(2)
S(3)C(6)S(4)
75.57(11)
104.62(10)
179.53(10)
176.38(9)
104.02(10)
75.80(9)
86.2(4)
85.8(4)
85.4(4)
86.2(3)
112.3(6)
112.1(6)
Anions
Cl(1)Tl(1)Cl(2)c
Cl(2)Tl(1)Cl(2)c
Cl(3)Tl(2B)Cl(6)
Cl(3)Tl(2B)Cl(3)d
Cl(5)Tl(2B)Cl(6)
Cl(5)Tl(2B)Cl(3)d
Cl(6)Tl(2B)Cl(3)d
Angle
Cl(1)Tl(1)Cl(2)
Cl(1)Tl(1)Cl(1)c
Cl(3)Tl(2A)Cl(4)
Cl(3)Tl(2A)Cl(3)d
Cl(3)Tl(2A)Cl(4)d
Cl(4)Tl(2A)Cl(4)d
Cl(3)Tl(2B)Cl(5)
103.22(9)
130.58(12)
114.0(3)
101.3(2)
111.5(3)
107.15(10)
102.47(13)
106.4(6)
108.1(2)
108.9(9)
114.9(6)
105.7(6)
104.9(6)
112.3(6)
Angle
ϕ, deg
ϕ, deg
Cation
Au(1)S(1)S(2)C(1)
Au(1)S(3)S(4)C(6)
S(1)Au(1)C(1)S(2)
S(3)Au(1)C(6)S(4)
S(1)C(1)N(1)C(2)
S(1)C(1)N(1)C(5)
S(2)C(1)N(1)C(2)
S(2)C(1)N(1)C(5)
S(3)C(6)N(2)C(7)
S(3)C(6)N(2)C(10)
S(4)C(6)N(2)C(7)
178.3(7)
171.4(6)
178.5(6)
172.4(5)
3.7(18)
–176.3(12)
–7.9(18)
–5.0(13)
–175.6(7)
172.2(7)
1.5(13)
S(4)C(6)N(2)C(10)
172.1(11)
a
b
c
d
a
b
c
* Symmetry transforms: –x, 1 – y, –z; 1 + x, y, z; –x, –y, 1 – z; 1 + x, y, z – 1 (I); 1/2 – x, 1 – y, z; x, 1/2 – y, 3/2 – z; 1/2 – x,
d
–y, z; x, 1/2 – y, 1/2 – z (II).
The unit cell of compound I contains one cen- atoms form the rectangular equatorial plane with the
trosymmetric binuclear molecule [Tl2{S2CN- sides S⋅⋅⋅S 2.967 Å (intraligand distance) and 4.068 Å
(interligand distance) and the angles somewhat devi-
ating from the right angle (85.36° and 94.64°), and the
metal atoms occupy the axial positions. In addition,
the octahedron discussed is distorted due to the com-
pression along the Tl–Tl axis (its length is 3.748 Å; for
comparison, the distances between the diagonally ori-
ented sulfur atoms are 4.838 and 5.226 Å).
(CH2)4O}2], which is the main structural unit of the
complex, and the formation of the molecule involves
two bridging dithiocarbamate ligands. The intradimer
interatomic Tl–Tl distance is 3.748 Å (Figs. 2, 3a).
Each thallium atom participating in the coordination
of all the four sulfur atoms (of two dithio ligands)
forms two stronger (Tl(1)–S(1) 3.015, Tl(1)–S(2)a
3.078 Å) and two weaker (Tl(1)–S(1)a 3.104, Tl(1)–
The positions of the thallium and carbon atoms of
S(2) 3.347 Å) bonds with the Dtc ligands. The binu- the =NC(S)S– groups in the structure of compound I
clear molecule of complex I is octahedral. Four sulfur are appreciably approached. The Tl–C interatomic
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 43 No. 10 2017

644
BREDYUK et al.
(a)
(b)
200
80
60
40
δ, ppm
13
Fig. 1. С MAS NMR spectra of complexes (a) I and (b) II. Scan number/rotation frequency (in kHz): 10240/10 and 1310/10,
respectively.
x
z
y
Fig. 2. Supramolecular crystal structure in compound I. Dashed lines show the secondary Tl···S bonds joining the polymer layers
of the binuclear [Tl {S CN(CH ) O} ] molecules into the three-dimensional polymeric framework.
2
2
2 4
2
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY
Vol. 43
No. 10
2017

THREE-DIMENSIONAL POLYMERIC THALLIUM(I) MORPHOLINEDITHIOCARBAMATE
(а)
645
Tl(1)a
O(1)
C(3)
C(2)
S(2)a
C(1)
S(2)
C(5)
C(4)
S(1)
S(1)a
N(1)
Tl(1)
S(2)b
O(1)d
O(1)c
(b)
Fig. 3. Structure of the octahedral binuclear molecule [Tl {S CN(CH ) O} ] with the vertex arrangement of the metal atoms
2
2
2 4
2
(70% probability ellipsoids). (a) Secondary intermolecular Tl···S bonds shown by dashed lines and (b) the projection onto the
[111] plane of the two-dimensional layer formed by the binuclear [Tl {S CN(CH ) O} ] molecules due to the nonequivalent
2
2
2 4
2
Tl···O secondary bonds.
distances are 3.40 and 3.52 Å (the sum of the van der between the planes of the [TlSS] and [CSS] half-
cycles are 136.5° and 138.3°.
In the discussed
Waals radii of the Tl and C atoms is 3.73 Å [27–29]).
This is favored by a fairly large SCS angle (119.0°) and
the inflection of the four-membered metallocycles
[TlS2C] along the S–S axis (Fig. 3а): the angles
binuclear
molecules
[Tl2{S2CN(CH2)4O}2], the coordination number of Tl
is 4. It is known that thallium(I) is characterized by
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 43 No. 10 2017

646
BREDYUK et al.
z
x
Fig. 4. Packing of structural units in the crystal of compound II (projection onto the plane xz). Positions of hollow channels inside
2+
the helical supramolecular chains ([Au {S CN(CH ) O} ] ) are gray-colored.
2
2
2 4
4
n
high coordination numbers, in particular, they reach Waals radii of the Tl and S atoms (3.76 Å [27–29]).
5–7 in the dithiocarbamate complexes [3–20]. The
discussed compound I is not exception, where the fur-
ther coordination saturation of thallium occurs due to
the oxygen atoms of the heterocyclic fragments. Each
oxygen atom nonsymmetrically interacts with the
thallium atoms of two adjacent binuclear molecules
Thus, as in the earlier described thallium(I) dimeth-
yldithiocarbamate [5], the overall coordination num-
ber of Tl in complex I is 7. The polyhedron of thallium
is a distorted one-capped trigonal prism formed by
five sulfur atoms and two oxygen atoms, and one S
atom is located beyond the face of the prism [31].
(Fig. 3b). The lengths of the secondary bonds1 Tl⋅⋅⋅O
are 3.112 and 3.175 Å (the sum of the van der Waals
radii of the Tl and O is 3.48 Å [27–29]). In turn, each
thallium atom additionally forms two nonequivalent
secondary bonds with the oxygen atoms of two dithio-
carbamate ligands increasing the coordination num-
ber of Tl to 6. Thus, a new type of secondary Tl⋅⋅⋅O
interactions is observed in thallium(I) morpholin-
edithiocarbamate. These interactions link the binu-
clear molecules into polymeric chains (angle TlTlTl
164.02°, interdimer distance Tl–Tl 4.794 Å) that are
combined into the two-dimensional polymer layer
(Fig. 3b). The interaction between the layers accom-
panied by the formation of the three-dimensional
framework occurs due to the secondary Tl⋅⋅⋅S bonds,
which are additionally formed by the thallium atoms
of each binuclear molecule with two adjacent layers
(Fig. 2). The discussed interactions are relatively weak.
Nevertheless, the Tl(1)⋅⋅⋅S(2)b bond length is 3.687 Å,
which is reliably shorter than the sum of the van der
The unit cell of complex II contains eight formula
units (Fig. 4). In the noncentrosymmetric complex
cation [Au{S2CN(CH2)4O}2]+, the coordination mode
of the MfDtc ligands that is close to S,S'-isobidentate
(Au–S 2.330–2.337 Å; Fig. 5a, Table 2) results in the
formation of the bicyclic system [CS2AuS2C] includ-
ing two four-membered metallocycles [AuS2C] with
the common gold atom. In the small-sized cycles
[AuS2C], the approached positions of the oppositely
lying atoms reflect the interatomic distances Au–C
2.796, 2.803 and S–S 2.860, 2.864 Å (the sums of the
van der Waals radii of the corresponding pairs of atoms
are 3.36 and 3.60 Å, respectively [27–29]). This fact
indicates the direct trans-annular interaction between
the discussed pairs of atoms and a high concentration
of the π-electron density inside the cycles. Some tetra-
hedral distortion is observed only in one of the
[AuS2C] cycles, because the torsion angles Au(1)–
S(3)–S(4)–C(6) and S(3)–Au(1)–C(6)–S(4) deviate
from 180° by 8.6° and 7.6°, respectively (Table 2). The
geometry of the chromophore [AuS4] is close to the
planar tetragonal one, to which the low-spin intraor-
bital dsp2-hybrid state of gold(II) corresponds (coordi-
nation number of Au is 4).
1
The concept of secondary bonds was first proposed [30] for the
description of interactions characterized by the distances com-
parable with the sums of the van der Waals radii of the corre-
sponding atoms.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY
Vol. 43
No. 10
2017

THREE-DIMENSIONAL POLYMERIC THALLIUM(I) MORPHOLINEDITHIOCARBAMATE
(а)
647
S(3)
S(1)
C(2)
C(8)
C(7)
N(2)
C(3)
O(1)
C(4)
N(1)
Au(1)
C(6)
C(1)
O(2)
C(10)
C(9)
C(5)
S(2)
S(4)
(b)
Cl(1)
Cl(2)
Cl(3)d
Tl(2B)
Cl(3)
Tl(2B)d
Tl(1)
Tl(2A)
Cl(5)d
Cl(5)
Cl(4)d
Cl(2)c
Cl(4)
Cl(1)c
Cl(6)d
Cl(6)
+
Fig. 5. (a) Structures of the complex cation [Au{S CN(CH ) O} ] (50% probability ellipsoids) and (b) isomeric complex anions
2
2 4
2
–
[TlCl ] of the Tl(1) and Tl(2) atoms (dashed lines show the structural positions of statistically distributed atoms in alternative
orientations of the Tl(2) anion: populations of positions are 0.50 for A, 0.25 for B, and 0.25 for В ; 50% probability ellipsoids).
4
d
The anionic moiety of complex II is presented by sented by the Г-shaped configuration: the bisector axes
two structurally nonequivalent discrete tetrachloroth- of the mononuclear cations passing through the CAuC
AuS C] form an
allate(III) ions (Fig. 5b) characterized by distorted tet- atoms in the bicyclic fragments [CS2
angle of 95° on the projection (Fig. 6). In t2he discussed
binuclear cation (Au–Au 4.331 Å), each gold atom
exists in the environment of five sulfur atoms (configu-
ration of an extended tetragonal pyramid). The pairs of
the heterocyclic N(CH2)4O fragments are characterized
by the opposite spatial orientation relative to the planes
of the [AuS4] chromophores due to interligand repul-
sion forces (Fig. 7).
rahedral structures (sp3-hybrid state of the central
thallium atoms). All ClTlCl bond angles deviate
appreciably from the ideal tetrahedral value (101.3°–
130.6°), and the Tl–Cl bond lengths range from 2.302
to 2.490 Å. The Tl–Cl bonds are nonequivalent in
pairs in both anions discussed. The structural situa-
tion in the anions containing the Tl(2) atom is
impeded by the fact that the thallium and chlorine
atoms (Cl(4) and Cl(4)d) are statistically distributed
between three structural positions А, В, and Вd in a
ratio of 0.50 : 0.25 : 0.25 (Fig. 5b, Table 2).
In turn, each binuclear cation forms two pairs of less
strong secondary Au⋅⋅⋅S bonds with the adjacent dimers
(Au(1)⋅⋅⋅S(2)a and Au(1)a⋅⋅⋅S(2) 3.576 Å) (Fig. 7). Note
that the S(2) atoms of the second MfDtc ligand partic-
ipate in these secondary interactions and lie together
with the S(4) atom at the same side of the central gold
atom. The simultaneous participation in the secondary
interactions of the S(4) and S(2) atoms cis-oriented in
the [AuS4] chromophore leads to the “twisting” of the
gold(III) cations to form the supramolecular cation-
cationic chain ([Au2{S2CN(CH2)4O}4]2+)n of the helical
type oriented toward the crystallographic axis y. Two
binuclear cations [Au2{S2CN(CH2)4O}4]2+ (or four
Owing to the pairs of the symmetric secondary
bonds Au(1)⋅⋅⋅S(4)b and Au(1)b⋅⋅⋅S(4) (a distance of
3.559 Å somewhat exceeds the sum of the van der Waals
radii of the sulfur and gold atoms equal to 3.46 Å [27–
29]), the interaction between the adjacent gold(III) cat-
ions results in their joining into dimeric aggregates
[Au2{S2CN(CH2)4O}4]2+ with the angular orientation
of the mononuclear fragments and the planes of the
[AuS4] chromophores retained parallel. It is seen from
the projection on the plane xz that the mutual spatial
orientation of the [Au{S2CN(CH2)4O}2]+ cations is pre- mononuclear cations [Au{S2CN(CH2)4O}2]+) form the
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 43 No. 10 2017

648
BREDYUK et al.
S(1)
S(2)
Au(1)
S(4)b
S(3)
95°
S(4)
S(3)b
Au(1)b
S(1)b
S(2)b
2+
Fig. 6. Projection of the structure of the binuclear [Au {S CN(CH ) O} ] cation on the plane xz.
2
2
2 4
4
full coil of the helix, which looks as a four-leafed aggre- to the calculated value (60.12%) for thallium(I) sul-
gate in the projection on the plane xz (Fig. 4). A hollow fide.
channel with a cross section of ~3.1 × 2.5 Å lies inside
The DSC curve exhibits several thermal effects
each helical chain (shown by gray in Fig. 4). In the
(Fig. 8b). The first intensive endothermic effect with
chain discussed, each gold atom builds up its polyhe-
an extreme at 264.5°C (extrapolated temperature
dron to the extended octahedron [AuS6] (angle
261.8°C) should be assigned to the melting of com-
S⋅⋅⋅Au⋅⋅⋅S 177.70°) due to two secondary Au⋅⋅⋅S bonds.
The interdimer Au–Au distance in the discussed chain
is 3.993 Å, and the angle AuAuAu is 129.20°. In the pro-
jection on the plane xz, the bisector axes of the adjacent
[Au{S2CN(CH2)4O}2]+ cations of different binuclear
cations form an angle of 85°. Structurally nonequivalent
tetrachlorothallate(III) ions [TlCl4]– participate in the
spatial isolation of the supramolecular helical chains
([Au2{S2CN(CH2)4O}4]2+)n and are localized in the
bulk between the chains.
pound I. For independent determination in a glass
capillary, the melting of the complex was established
in the range of 262–264°C. The broadened asymmet-
ric thermal effect with an extrapolated temperature of
303.8°C is attributed to the thermolysis of the sample
and evaporation of the decomposition products: its
extreme at 324.2°C corresponds to the maximum rate
of mass loss. The use of differentiation did not reveal
the internal structure of the discussed thermal effect.
The high-temperature region of the DSC curve con-
tains an additional endothermic effect (with an
extreme at 448.5°C) caused by the melting of Tl2S
(reference data: mp = 448.9°C [32]).
The thermal behavior of complexes I and II was
studied by the STA method with the detection of the
TG and DSC curves. Compound I is thermally stable
up to the melting point. A significant mass loss is
detected in the TG curve (Fig. 8a) only after melting.
As the temperature increases, the smooth mass loss
transits to the steeply descending region of the TG
curve (~290–350°C), showing an intense thermolysis
Two main steps of the mass loss can be distin-
guished in the TG curve of compound II (Fig. 9a).
The first step (~200–290°C) is caused by the thermol-
ysis of the complex simultaneously by the
[Au{S2CN(CH2)4O}2]+ cation (with gold(III) reduc-
of compound I with the formation of Tl2S, being the tion to the elemental state) and [TlCl4]– anion (with
final product of the thermal transformations of thal- TlCl release). The inflection point at 245°C divides
lium(I) dithiocarbamates [17, 19]. The weight of the this region of the TG curve into two sections. The
residue is 60.13% of the initial mass and corresponds mass loss before the inflection point (28.13%) suggests
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY
Vol. 43
No. 10
2017

THREE-DIMENSIONAL POLYMERIC THALLIUM(I) MORPHOLINEDITHIOCARBAMATE
S(2)e
649
S(4)d
Au(1)d
S(2)a
Au(1)a
S(4)a
S(4)
Au(1)
S(2)
Au(1)b
S(4)b
S(2)c
2+
b
Fig. 7. Two-unit fragment of the cation-cationic polymeric helical chain ([Au {S CN(CH ) O} ] ) oriented along the crystal-
2
2
2 4
4
n
a
c
lographic axis y; secondary bonds Au⋅⋅⋅S are shown by dash. Symmetry codes: 1/2 – x, 1 – y, z; x, 1/2 – y, 3/2 – z; 1/2 – x,
d
e
y – 1/2, 3/2 – z; 1/2 – x, 1/2 + y, 3/2 – z; x, 3/2 – y, 3/2 – z.
TG, %
DSC, mW/mg
а
4
100
446.7°C
3
448.5°C
90
2
–39.03%
303.8°C
261.8°C
80
70
60
1
324.2°C
b
0
264.5°C
60.13%
–1
100
200
300
400 T, °C
Fig. 8. (a) TG and (b) DSC curves for complex I.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 43 No. 10 2017

650
BREDYUK et al.
ТG, %
DSC, mW/mg
3.5
а
100
90
80
70
60
50
40
30
–28.13%
546.4°C
3.0
2.5
2.0
426.6°C
–11.65%
428.8°C
1.5
1.0
0.5
0
1054.7°C
–31.56%
245.7°C
215.1°C
1063.7°C
22.56%
239.2°C
221.6°C
b
–5.74%
200
400
600
800
1000
T, °C
Fig. 9. (a) TG and (b) DSC curves for complex II.
that the initial stage of the thermal destruction of com- the thermolysis of compound II and is accompanied
plex II is related to the elimination of two alkoxyl frag- by the formation of TlCl. Since the second step of
mass loss is mainly related to the evaporation of TlCl
and the corresponding region of the DSC curve
includes the endothermic effect of its melting with the
extreme at 428.8°C (reference mp = 431°C [32]), it
can be concluded that the discussed exothermic effect
is due to the crystallization of the formed thallium(I)
chloride. The weak endothermic effect with the
extreme at 546.4°C is related to the evaporation of
thallium(I) chloride. The endothermic effect with the
extreme at 1063.7°C showing the melting of reduced
gold is observed in the high-temperature section of the
DSC curve.
ments (=CHCH2)2O to form the intermediate cation
[Au(S2CNH2)2]+ [33] and three chlorine atoms (calcd.
28.62%). Since the thermolysis of compound II starts
at 200°C, TlCl3 released by the anion begins to decom-
pose already at the moment of release. According to
published data [32], at the temperature higher than
150°C TlCl3 decomposes to TlCl and chlorine.) The
region of gold reduction to metal follows after 245°C
(calcd. mass loss 21.24%) and is conjugated with the
second step of the TG curve (mainly caused by the
evaporation of TlCl, calcd. 27.64%) and subsequent
reaching the smooth region of the final desorption of
volatile thermolysis products. The total experimen-
tally detected mass loss in three discussed regions of
the TG curve is equal to 48.95% (11.65 + 31.56 +
5.74%), which completely corresponds to a total cal-
culated value of 48.88% (21.24 + 27.64%). At the com-
pletion of the process at 1100°C, the weight of the res-
idue is 22.56% of the initial value, which is close to the
calculated value equal to 22.70% for reduced metallic
gold.
ACKNOWLEDGMENTS
This work was supported in part by the Presidium
of the Far East Branch of the Russian Academy of Sci-
ences (program “Dal’nii Vostok,” project no. 15-I-3-
001).
REFERENCES
The DSC curve in the low-temperature range
shows two thermal effects: the endothermic effect with
an extreme at 221.6°C and the exothermic effect at
245.7°C (Fig. 9b). The endothermic effect with an
extrapolated temperature of 215.1°C is assigned to the
melting of complex II with decomposition. For inde-
pendent determination in a glass capillary, the unsta-
ble character of the sample (irreversible blackening) is
detected at 215°C, whereas the melting with evident
signs of decomposition falls on a range of 220–221°C.
It is important to mention when discussing the nature
of the exothermic effect that the latter is projected
onto the first step of the TG curve corresponding to
1. Riley, J.P. and Siddiqui, S.A., Anal. Chim. Acta, 1986,
vol. 181, p. 117.
2. Elson, C.M. and Albuquerque, C.A.R., Anal. Chim.
Acta, 1982, vol. 134, p. 393.
3. Nilson, L. and Hesse, R., Acta Chem. Scand., 1963,
vol. 23, no. 6, p. 1951.
4. Jennische, P., Olin, Å., and Hesse, R., Acta Chem.
Scand., 1972, vol. 26, no. 7, p. 2799.
5. Jennische, P. and Hesse, R., Acta Chem. Scand., 1973,
vol. 27, no. 9, p. 3531.
6. Anacker-Eickhoff, H., Jennische, P., and Hesse, R.,
Acta Chem. Scand., Ser. A, 1975, vol. 29, no. 1, p. 51.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY
Vol. 43
No. 10
2017

THREE-DIMENSIONAL POLYMERIC THALLIUM(I) MORPHOLINEDITHIOCARBAMATE
651
7. Pritzkow, H. and Jennische, P., Acta Chem. Scand., Ser. 21. Ivanov, A.V., Bredyuk, O.A., Loseva, O.V., and
A, 1975, vol. 29, no. 1, p. 60.
Rodina, T.A., Russ. J. Coord. Chem., 2015, vol. 41,
no. 2, p. 108.
8. Elfwing, E., Anacker-Eickhoff, H., Jennische, P., and
Hesse, R., Acta Chem. Scand., Ser. A, 1976, vol. 30,
no. 5, p. 335.
22. Ivanov, A.V., Bredyuk, O.A., Loseva, O.V., and
Antzutkin, O.N., Russ. J. Inorg. Chem., 2016, vol. 61,
no. 6, p. 755.
9. Hong, S.-H. and Jennische, P., Acta Chem. Scand., Ser.
A, 1978, vol. 32, no. 4, p. 313.
23. Byr’ko, V.M. Ditiokarbamaty, Moscow: Nauka, 1984.
10. Alexander, N., Ramalingam, K., and Rizzoli, C.,
24. Pines, A., Gibby, M.G., and Waugh, J.S., J. Chem.
Inorg. Chim. Acta, 2011, vol. 365, no. 1, p. 480.
Phys., 1972, vol. 56, no. 4, p. 1776.
11. Akhbari, K. and Morsali, A., Coord. Chem. Rev., 2010,
25. Bruker, APEX2 (version 1.08), SAINT (version 7.03),
SADABS (version 2.11), SHELXTL (version 6.12),
Madison: Bruker AXS Inc., 2004.
26. Khimicheskaya entsiklopediya (Chemical Encyclopedia),
Zefirov, N.S., Ed., Moscow: Bolshaya Rossiiskaya
Entsiklopediya, 1995.
27. Pauling, L., The Nature of the Chemical Bond and the
Structure of Molecules and Crystals, London: Cornell
Univ., 1960.
28. Bondi, A., J. Phys. Chem., 1964, vol. 68, no. 3, p. 441.
29. Bondi, A., J. Phys. Chem., 1966, vol. 70, no. 9, p. 3006.
vol. 254, nos 17–18, p. 1977.
12. Ramalingam, K., Rizzoli, C., and Alexander, N., Mon-
atsh. Chem., 2013, vol. 144, no. 9, p. 1329.
13. Sivagurunathan, G.S., Ramalingam, K., and
Rizzoli, C., Polyhedron, 2013, vol. 65, p. 316.
14. Gomathi, G., Thirumaran, S., and Ciattini, S., Polyhe-
dron, 2015, vol. 102, p. 424.
15. Kumar, V., Singh, V., Gupta, A.N., Drew, M.G.B.,
and Singh, N., Dalton Trans., 2015, vol. 44, no. 4,
p. 1716.
16. Ramalingam, K., Rizzoli, C., and Sivaguruna-
30. Alcock, N.W., Adv. Inorg. Chem. Radiochem., 1972,
than, G.S., New J. Chem., 2016, vol. 40, no. 3, p. 2489.
vol. 15, no. 1, p. 1.
17. Manar, K.K., Rajput, G., Yadav, M.K., Yadav, C.L.,
Kumari, K., Drew, M.G.B., and Singh, N., Chem.
Select., 2016, vol. 1, no. 18, p. 5733.
18. Ivanov, A.V., Bredyuk, O.A., Gerasimenko, A.V., and
Antzutkin, O.N., Dokl. Phys. Chem., 2008, vol. 420,
no. 2, p. 130.
19. Rodina, T.A., Ivanov, A.V., Bredyuk, O.A., and Gera-
simenko, A.V., Russ. J. Coord. Chem., 2009, vol. 35,
no. 3, p. 170.
31. Urusov V.S. Teoreticheskaya kristallokhimiya (Theoret-
ical Crystal Chemistry), Moscow: Izd. MGU, 1987.
32. Lidin, R.A., Molochko, V.A., and Andreeva, L.L. Khi-
micheskie svoistva neorganicheskikh veshchestv (Chemi-
cal Properties of Inorganic Substances) Moscow:
Khimiya, 2000.
33. Ivanov, A.V., Loseva, O.V., Rodina, T.A., et al., Russ.
J. Coord. Chem., 2016, vol. 42, no. 2, p. 104.
20. Ivanov, A.V., Bredyuk, O.A., Gerasimenko, A.V., et al.,
Translated by E. Yablonskaya
Russ. J. Coord. Chem., 2006, vol. 32, no. 5, p. 339.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 43 No. 10 2017