Syntheses and structures of heterobimetallic complexes derived from [Ga(edt)2]- as a metalloligand (edt = -SC 2H4S-): Potential precursors for ternary materials MGaS2 (M = Cu or Ag)

Article abstract of DOI:10.1016/j.ica.2010.09.044

Metathesis reaction between equimolar amount of [Et₄N][GaCl ₄] and Na₂edt in methanol resulted in the formation of the dichloro complex [Et₄N][Ga(edt)Cl₂] (1), whereas reaction of [Et₄N][GaCl₄] with two equivalents of Na ₂edt in methanol gave the complex [Et₄N][Ga(edt) ₂] (2) which can act as a metalloligand. Treatment of 2 with M(PPh₃)₂NO₃ in DMF/CH₂Cl₂ afforded the heterobimetallic complexes [Ga(edt)₂M-(PPh ₃)₂] (M = Cu 3, Ag 4) in moderate yields. The structures of 1-4 were determined by single-crystal X-ray diffraction analyses. Both [Ga(edt)Cl₂]^- and [Ga(edt)₂]^- anions have a distorted tetrahedral geometry. The former consists of one five-membered ring formed by chelating dithiolate and two terminal chloride atoms while the latter consists of two five-membered rings formed by two the chelating dithiolates. Complexes 3 and 4 consist of metalloligand [Ga(edt) ₂]^- anion chelated to [M(PPh₃) ₂]⁺ via the sulfur atoms. Both tetrahedrally coordinated Ga and Cu(Ag) atoms are bridged by two sulfur atoms, forming a planar "GaS₂M" (M = Cu, Ag) core. Thermogravimetry analysis revealed that heterobimetallic complexes 3 and 4 decomposed to give the corresponding ternary metal sulfide materials.

Full text of DOI:10.1016/j.ica.2010.09.044

Inorganica Chimica Acta 365 (2011) 414–418
Contents lists available at ScienceDirect
Inorganica Chimica Acta
journal homepage: www.elsevier.com/locate/ica
Syntheses and structures of heterobimetallic complexes derived from [Ga(edt)2]ꢀ
as a metalloligand (edt = ꢀSC2H4Sꢀ): Potential precursors for ternary materials
MGaS2 (M = Cu or Ag)
⇑
Yan-Gong Han, Chao Xu, Taike Duan, Qian-Feng Zhang
Institute of Molecular Engineering and Applied Chemistry, Anhui University of Technology, Ma’anshan, Anhui 243002, PR China
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 23 May 2009
Received in revised form 3 July 2010
Accepted 28 September 2010
Available online 8 October 2010
Metathesis reaction between equimolar amount of [Et4N][GaCl4] and Na2edt in methanol resulted in the
formation of the dichloro complex [Et4N][Ga(edt)Cl2] (1), whereas reaction of [Et4N][GaCl4] with two
equivalents of Na2edt in methanol gave the complex [Et4N][Ga(edt)2] (2) which can act as a metalloli-
gand. Treatment of 2 with M(PPh3)2NO3 in DMF/CH2Cl2 afforded the heterobimetallic complexes
[Ga(edt)2M-(PPh3)2] (M = Cu 3, Ag 4) in moderate yields. The structures of 1–4 were determined by sin-
gle-crystal X-ray diffraction analyses. Both [Ga(edt)Cl2]ꢀ and [Ga(edt)2]ꢀ anions have a distorted tetrahe-
dral geometry. The former consists of one five-membered ring formed by chelating dithiolate and two
terminal chloride atoms while the latter consists of two five-membered rings formed by two the chelat-
ing dithiolates. Complexes 3 and 4 consist of metalloligand [Ga(edt)2]ꢀ anion chelated to [M(PPh3)2]+ via
the sulfur atoms. Both tetrahedrally coordinated Ga and Cu(Ag) atoms are bridged by two sulfur atoms,
forming a planar ‘‘GaS2M” (M = Cu, Ag) core. Thermogravimetry analysis revealed that heterobimetallic
complexes 3 and 4 decomposed to give the corresponding ternary metal sulfide materials.
Ó 2010 Elsevier B.V. All rights reserved.
Keywords:
Synthesis
Gallium
Copper
Silver
Metalloligand
Metal sulfide materials
1. Introduction
precursors to nanocrystalline photovoltaic materials MInS2
(M = Cu, Ag) [15,18–21]. The precursors should have the correct
In contrast to a few indium thiolates which are important pre-
cursors for sulfur-containing indium compounds, analogous gal-
lium thiolates are extremely rare [1–5]. There are several reports
on the use of homoleptic gallium alkylthiolate and arylthiolate
complexes as precursors of sulfur-rich gallium sulfide films by
chemical vapor deposition [5–9]. Although solid-state thiogallates
have been under increased investigation in the past two decades
[10–12], the chemistry of soluble molecular gallium thiolate com-
pounds has not been extensively studied to date [13,14]. Similar to
analogous indium tetra-thiolates which reacted with coinage-met-
als to afford bimetallic adducts as single-source precursors to the
ternary semiconductors such as CuInS2, AgInS2 and AgIn5S8 [15–
21], gallium tetra-thiolates may be reasonably speculated to coor-
dinate with coinage-metals via sulfur atoms of thiolates. Thus, the
ability of homolepic [In(SR)4]ꢀ or [Ga(SR)4]ꢀ as a metalloligand to-
ward coinage-metals is obviously due to electron-rich sulfur affin-
ity and small steric hindrance in the alkylthiolate moieties.
Remarkably, Kanatizidis et al. have shown that indium-tetrathio-
lates [In(SR)4]ꢀ reacted with copper- or silver-phosphine species
to produce the ternary complexes which are effective single-source
M/In ratio of 1:1 and should decompose in simple steps to the de-
sired products [22,23]. Fenske and coworkers have successfully
isolated series of ternary chalcogenide high-nuclear clusters con-
taining groups 11 and 13 metals [24,25]. However, it is very diffi-
cult to control the ratio of the two metals in the resulting clusters
no matter how the ligands and reaction conditions varied. This
may be partly due to the difficulty in obtaining heterometallic pre-
cursor complexes with the mixed metals in the proper ratio [26]. In
order to prepare complexes with M/Ga (M = Cu, Ag) ratio of 1:1, we
selected spirocyclic [Ga(edt)2]ꢀ anion (edt = ꢀSC2H4Sꢀ) as a staring
material to coordinate with the cationic [M(PPh3)2]+ species
which then gave the designed neutral bimetallic complexes. The
results and molecular structures of the heterobimetallic coinage-
metal/gallium complexes that are potential precursors to MGaS2
(M = Cu or Ag) ternary materials are described in this paper.
2. Experimental
2.1. Materials and measurements
All experiments were performed with oven-dried glassware un-
der a purified nitrogen atmosphere using standard Schlenk tech-
niques. All reagents, unless otherwise stated, were purchased as
⇑
Corresponding author. Tel./fax: +86 555 2312041.
E-mail address: zhangqf@ahut.edu.cn (Q.-F. Zhang).
0020-1693/$ - see front matter Ó 2010 Elsevier B.V. All rights reserved.
doi:10.1016/j.ica.2010.09.044

Y.-G. Han et al. / Inorganica Chimica Acta 365 (2011) 414–418
415
analysis grade and were used without further purification. [Et4N]
2.5. Preparation of [Ga(edt)2Ag(PPh3)2] (4)
[GaCl4] [27], Cu(PPh3)2NO3 [28], and Ag(PPh3)2NO3 [29] were pre-
pared according to the literature methods. All elemental analyses
were carried out using a Perkin–Elmer 2400 CHN analyzer. Infrared
spectra were recorded on a Digilab FTS-40 spectrophoto-meter
with use of pressed KBr pellets, and positive FAB mass spectra were
recorded on a Finnigan TSQ 7000 spectrometer. NMR spectra were
recorded on a Bruker ALX 300 spectrometer operating at 300 and
121.5 MHz for 1H and 31P, respectively, and chemical shift (d,
ppm) were reported with reference to SiMe4 (1H) and H3PO4
Compound 4 was prepared similarly as described for 3 using
Ag(PPh3)2NO3 (347 mg, 0.5 mmol) instead of Cu(PPh3)2NO3. Color-
less block crystals were obtained in a yield of 52% (233 mg). IR
(KBr, cmꢀ1): (P–C) 596 (s), 530 (s), 499 (m). 1H
m(C–S) 649 (m), m
NMR (CDCl3, ppm): d 2.78–2.82 (br, s, 8H, CH2 in edt), 7.34–7.49
(m, 30H, Ph). 31P NMR (CDCl3, ppm): d 5.31 (d, J = 13.4 Hz). MS
(FAB): m/z 886 (M+), 624 (M+ꢀPPh3), 362 (M+ꢀ2PPh3). Anal. Calc.
for C40H38P2S4GaCu: C, 54.2; H, 4.32%. Found: C, 54.1; H, 4.28%.
(
31P). Thermogravimetric analysis (TGA) was performed by using
a Delta TGA instrument.
2.6. X-ray crystallographic study
The structures of [Et4N][Ga(edt)Cl2] (1), [Et4N][Ga(edt)2] (2),
[Ga(edt)2Cu(PPh3)2] (3), and [Ga(edt)2Ag(PPh3)2] (4) were deter-
mined by single-crystal X-ray diffraction technique. Diffraction
data were collected on a Bruker SMART Apex CCD diffractometer
2.2. Preparation of [Et4N][Ga(edt)Cl2] (1)
To a slurry of [Et4N][GaCl4] (342 mg, 1.00 mmol) in methanol
(10 ml) was added dropwise Na2edt (145 mg, 1.05 mmol) (ob-
tained from the reaction of H2edt and MeONa in a 1:2 mol ratio)
in 10 ml of methanol with stirring. The mixture was stirred at room
temperature for 30 min. Fine white solids were observed. The solu-
tion was cooled to 0 °C. The precipitates were collected by suction
filtration and washed twice with 10 ml portions of diethyl ether.
White air-stable solids were obtained and further recrystallized
from DMF/diethyl ether to give colorless block crystals of 1 in
with Mo Ka radiation (k = 0.71073 Å) at 296 K using an x scan
mode. The collected frames were processed with the software
SAINT [30]. The data was corrected for absorption using the program
SADABS [31]. Structures were solved by Direct Methods and refined
by full-matrix least-squares on F2 using the SHELXTL software pack-
age [32]. All non-hydrogen atoms were refined anisotropically.
The positions of all hydrogen atoms were generated geometrically
(Csp3–H = 0.96, Csp2–H = 0.93 Å) and included in the structure factor
calculations with assigned isotropic displacement parameters but
were not refined. The Flack parameter were 0.00 and 0.01(1) for
1 and 2, respectively, indicating that the correct enantiomorphs
have been selected in both structures. Further details of the data
determination, crystal data and structure refinement parameters
are summarized in Table 1.
3 days. Yield: 311 mg, 85%. IR (KBr, cmꢀ1):
m
(C–S) 644 (m). 1H
NMR (DMSO-d6, ppm): d 1.02 (q, J = 6.2 Hz, 12H, CH3 in Et4N),
2.75 (br, s, 4H, CH2 in edt), 2.91 (t, J = 7.8 Hz, 8H, CH2 in Et4N).
MS (FAB): m/z 233 (M+ꢀ[Et4N]), 163 ([Ga(edt)]++1). Anal. Calc. for
C10H24NCl2S2Ga: C, 33.1; H, 6.66; N, 3.86%. Found: C, 33.0; H,
6.62; N, 3.81%.
3. Results and discussion
2.3. Preparation of [Et4N][Ga(edt)2] (2)
A summary of our synthesis was presented in Scheme 1.
Metathesis reaction between equimolar amount of [Et4N][GaCl4]
and Na2edt in methanol resulted in the formation of the dichloro
complex [Et4N][Ga(edt)Cl2] (1). Treatment of [Et4N][GaCl4] with
two equivalents of Na2edt in methanol afforded [Et4N][Ga(edt)2]
(2) in a yield of 87%. The analogous indium complex [Et4N]
[In(edt)2] was previously reported by Kanatzidis and co-workers
[4]. Complexes 1 and 2 were stable in both the solid state and solu-
tion. Both were soluble in DMF, slightly soluble in THF and MeCN,
but sparingly soluble in common solvents. The infrared spectra of
To a slurry of [Et4N][GaCl4] (342 mg, 1.00 mmol) in methanol
(10 ml) was added dropwise Na2edt (290 mg, 2.10 mmol) in
10 ml of methanol with stirring. The mixture was stirred at room
temperature for 45 min. Fine white solids were observed. The solu-
tion was then stirred for another 30 min. The precipitates were col-
lected by suction filtration and washed twice with 10 ml portions
of diethyl ether. Recrystallization from DMF/diethyl ether afforded
colorless block crystals of 1 suitable for single-crystal X-ray analy-
sis. Yield: 346 mg, 87%. IR (KBr, cmꢀ1): (C–S) 652 (m). 1H NMR
m
(DMSO-d6, ppm): d 1.04 (q, J = 6.4 Hz, 12H, CH3 in Et4N), 2.78 (br,
s, 8H, CH2 in edt), 2.93 (t, J = 7.6 Hz, 8H, CH2 in Et4N). MS (FAB):
m/z 254 (M+ꢀ[Et4N]). Anal. Calc. for C12H28NS4Ga: C, 37.5; H,
7.34; N, 3.64%. Found: C, 37.2; H, 7.30; N, 3.64%.
both complexes displayed the characteristic
m(C–S) stretching
vibration of the coordinated edt2ꢀ at 644 and 652 cmꢀ1. The 1H
NMR spectra of 1 and 2 displayed a broad singlet at d 2.75 and
2.78 ppm, respectively, which are assigned to the protons of the
edt2ꢀ moiety. The molecular ions corresponding to [Ga(edt)Cl2]ꢀ
and [Ga(edt)2]ꢀ with the characteristic isotopic distribution pat-
terns can be observed at m/z 233 and 254 in the mass spectra of
1 and 2, respectively.
2.4. Preparation of [Ga(edt)2Cu(PPh3)2] (3)
To a solution of 2 (192 mg, 0.50 mmol) in 10 ml of DMF was
slowly added Cu(PPh3)2NO3 (326 mg, 0.5 mmol) in 20 ml of CH2Cl2,
and the mixture was stirred for 2 h. After filtration, the clear solu-
tion was layered with 30 ml of diethyl ether. Colorless prism and
block crystals of 3 were obtained after 3 days. Yield: 240 mg
(57%). Both crystals were suitable for single-crystal X-ray diffrac-
tion. Different unit cells of two shape crystals were obtained and
two sets of data were collected for structure solution. IR (KBr,
The structures of 1 and 2 were confirmed by X-ray diffraction
analysis. The crystal structure of the [Ga(edt)Cl2]ꢀ anion in 1 is
shown in Fig. 1 and selected bond lengths and angles are summa-
rized in Table 2. Complex 1 crystallized in monoclinic crystal system
with non-centro-symmetric space group P21. 1 consists of well
separated cations and anions. There are two perpendicular arrange-
ments for the molecules in the crystal with slightly different confor-
mations, but no significant differences in bonding parameters
between two molecules (A and B) were found. The anion in 1 has
a distorted tetrahedral geometry that is similar to those of the
dichloro anions in [N(Ph2PQ)2GaCl2] (Q = S, Se) [33] and
cmꢀ1): (P–C) 598 (s), 532 (s), 501 (m). 1H NMR
m(C–S) 641 (m), m
(CDCl3, ppm): d 2.76–2.84 (br, s, 8H, CH2 in edt), 7.26–7.41
(m, 30H, Ph). 31P NMR (CDCl3, ppm): d ꢀ1.94. MS (FAB): m/z
842 (M+), 580 (M+ꢀPPh3), 318 (M+ꢀ2PPh3). Anal. Calc. for
[(PPh3)4Pt2(
the five-membered gallacycles adopts approximately planar
l
3-S)3GaCl2][GaCl4] [34]. The chelating edt2ꢀ ligand in
C40H38P2S4GaCu: C, 57.0; H, 4.55%. Found: C, 56.8; H, 4.51%.

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Y.-G. Han et al. / Inorganica Chimica Acta 365 (2011) 414–418
Table 1
Crystal data and structure refinement for complexes [Et4N][Ga(edt)Cl2] (1), [Et4N][Ga(edt)2] (2), [Ga(edt)2Cu(PPh3)2] (3), and [Ga(edt)2Ag(PPh3)2] (4).
Complex
1
2
3a
3b
4
Formula
Formula weight
Crystal system
Space group
a (Å)
C
10H24NCl2S2Ga
C12H28NS4Ga
384.31
orthorhombic
P212121
8.5777(1)
10.4767(2)
20.7841(3)
C40H38P2S4GaCu
842.14
monoclinic
P21/n
15.9012(3)
16.4144(4)
16.7762(3)
116.563(1)
3916.53(14)
4
C40H38P2S4GaCu
842.14
monoclinic
P21/n
10.5839(1)
23.2097(2)
15.6176(1)
91.978(1)
3834.16(5)
4
C40H38P2S4GaAg
886.47
monoclinic
P21/n
10.4472(1)
23.3945(2)
15.9664(2)
91.553(1)
3900.87(7)
4
363.04
monoclinic
P21
8.3164(3)
13.9425(6)
14.6567(6)
92.911(3)
1697.27(12)
4
b (Å)
c (Å)
b (°)
V (Å3)
1867.78(5)
4
1.367
Z
Dcalc (g cmꢀ3
)
1.421
1.428
1.459
1.509
Temperature (K)
F(0 0 0)
296(2)
752
2.161
296(2)
808
1.907
296(2)
1728
1.554
296(2)
1728
1.587
296(2)
1800
1.517
l
(Mo K
a
) mmꢀ1
No. reflections measured
No. unique reflections
No. observed reflections
No. parameters
17 194
7226
5048
197
34 161
4258
3759
167
38 311
8981
6646
433
37 985
8769
6579
433
38 675
8939
7066
433
Rint
0.0315
0.0271
0.0287
0.0333
0.0274
b
R1a, wR2 (I > 2
r(I))
0.0416, 0.0938
0.0695, 0.1057
1.003
0.00(0)
+0.409, ꢀ0.254
0.0289, 0.0692
0.0353, 0.0722
1.054
0.011(10)
+0.424, ꢀ0.269
0.0340, 0.0756
0.0554, 0.0837
1.029
0.0334, 0.0713
0.0534, 0.0783
1.016
0.0293, 0.0674
0.0429, 0.0730
1.015
R1a, wR2 (all data)
b
Goodness-of-fit (GOF)c
Flack value
Final difference in peaks (e Åꢀ3
)
+0.675, ꢀ0.789
+0.448, ꢀ0.240
+0.853, ꢀ0.604
P
h
P
a
b
c
R1
¼
jj Fo j ꢀ j Fc jj= j Fo j.
h
i
1=2
P
P
2
2
wR2
¼
wðj F2o j ꢀ j Fc2 j Þ = w j F2oj
.
i
1=2
P
2
GoF ¼
wðj Fo j ꢀ j Fc j Þ =ðNobs ꢀ Nparam
Þ
.
Cl
Ga
S
Cl
S
i
1
Cl
S
S
S
PPh3
iii
Ga
Cl
Ga
Cl
Cl
M
PPh3
S
ii
iv
S
M = Cu 3
Ag 4
Ga
S
S
S
2
Scheme 1. Reagents and conditions: (i) Na2edt/MeOH, (ii) 2Na2edt/MeOH, (iii) Na2edt/MeOH, (iv) M(PPh3)2NO3 (M = Cu, Ag)/DMF/CH2Cl2.
Table 2
Selected bond distances (Å) and bond angles (°) for 1.
Molecule A
Molecule B
Ga(1)–S(1)
Ga(1)–S(2)
Ga(1)–Cl(1)
Ga(1)–Cl(2)
S(1)–Ga(1)–S(2)
Cl(1)–Ga(1)–S(1)
Cl(1)–Ga(1)–S(2)
Cl(2)–Ga(1)–S(1)
Cl(2)–Ga(1)–S(2)
Cl(1)–Ga(1)–Cl(2)
2.2279(14)
2.2360(15)
2.2237(15)
2.1997(16)
99.63(6)
111.09(6)
115.74(6)
115.51(7)
112.89(7)
102.57(7)
Ga(2)–S(3)
Ga(2)–S(4)
Ga(2)–Cl(3)
Ga(2)–Cl(4)
S(3)–Ga(2)–S(4)
Cl(3)–Ga(2)–S(3)
Cl(3)–Ga(2)–S(4)
Cl(4)–Ga(2)–S(3)
Cl(4)–Ga(2)–S(4)
Cl(3)–Ga(2)–Cl(4)
2.2209(16)
2.2241(16)
2.2185(15)
2.2172(17)
100.46(7)
111.17(6)
114.41(7)
115.86(7)
112.21(7)
103.22(7)
geometry with deviations of 0.17 Å for molecule A and 0.03 Å for
molecule B from the least-squares planes. The terminal Ga–Cl bonds
in 1 [av. 2.2148(16) Å] are similar to those in [N(Ph2PS)2 GaCl2]
Fig. 1. A view of the [Ga(edt)Cl2]ꢀ anion in 1.

Y.-G. Han et al. / Inorganica Chimica Acta 365 (2011) 414–418
417
[2.1688(16) Å], [N(Ph2PSe)2GaCl2] [2.1470(15) Å], [N(Ph2PS)
{(EtO)2PO}GaCl2] [2.1766(6) Å] [33], and [(PPh3)4Pt2( 3-S)3GaCl2]
l
[GaCl4] [2.1853(3) Å] [34]. The crystal structure of [Ga(edt)2]ꢀ anion
in 2 is shown in Fig. 2. The anion in 2 has a highly distorted tetrahe-
dral geometry due to the restricting bite-size of chelating dithiolate,
which is similar to that of the anion in [PPh4][In(edt)2] [4]. The aver-
age Ga–S bond length [2.2612(9) Å] in 2 is in good agreement
with those in [(i-Pr)2NH2][Ga(S-i-Pr)4] [2.2678(6) Å] [14], [i-Pr4N]
[Ga(SEt)4] [2.264(3) Å] [13], and [Et4N][Ga(SPh)4] [2.257(3) Å]
[13]. The two five-membered chelate rings GaS2C2 are non-planar.
The average distance between sulfur atoms in different edt2ꢀ moie-
ties is ca. 3.8 Å.
Complex 2 was isolated in a high yield and may act as a metal-
loligand that coordinates with the cationic coinage-metal com-
plexes via the sulfur atoms, forming the neutral bimetallic
complexes Ga(edt)2ML2 (M = Cu, Ag; L = phosphine ligands). Under
this circumstance, treatment of 2 with M(PPh3)2NO3 in DMF/
CH2Cl2 afforded a homogeneous solution from which colorless
crystals of [Ga(edt)2M(PPh3)2] (M = Cu 3, Ag 4) were isolated in
moderate yields. The singlet at d ꢀ1.94 for 3 and the doublet at d
5.31 ppm for 4 in the 31P{1H} NMR spectra were downfield from
that of the free PPh3 ligand. The doublet in the 31P{1H} NMR spec-
trum of 4 is probably due to the coupling with 107Ag and 109Ag. The
FAB+ mass spectra of 3 and 4 exhibited molecular ions correspond-
ing to M+, M+ꢀPPh3 and M+ꢀ2PPh3 with characteristic isotopic dis-
tribution patterns.
The solid-state structures of complexes 3 and 4, as shown in
Figs. 3 and 4, respectively, were determined by X-ray crystallogra-
phy. The bond lengths and angles of the two complexes were com-
piled in Table 3 for comparison. The two different shaped crystals
of 3 analyzed by single-crystal X-ray diffraction have different unit
cells but with the same space group P21/n. As depicted by the
views of Fig. 3b and a, the Cuꢁ ꢁ ꢁGa distance of 2.9892(4) Å in 3b
is slightly shorter than that of 3.056(1) Å in 3a. Cu(1) or Ag(1) is
bonded to two PPh3 ligands and two edt2ꢀ through their sulfur do-
nor sites, forming a tetrahedral P2CuS2 or P2AgS2 core. Both tetra-
hedrally coordinated Ga and Cu(Ag) atoms are bridged by two
sulfur atoms of two edt2ꢀ, forming a planar four-membered
‘‘GaS2M” (M = Cu, Ag) ring. The average Ga–S–Cu angle in 3
(78.89(2)°) is comparable to that in [(PPh3)Cu(l-SC{O}Ph-S)(l-
SC{O}Ph-S,O)2Ga(SC{O}Ph)] (79.39(6)°) [35], but is smaller than
the average In-S-Cu angle in [(PPh3)2Cu(SEt)2In(SEt)2] (85.58(8)°)
[15]. The average Ga–S–Ag angle in 4 (79.54(2)°) is also smaller
than the average In–S–Ag angle in [(PPh3)2Ag(SMe)2In(SMe)2]
(84.16(3)°) [21]. The average Cu–S bond length in 3 is 2.4482(6)
Å and the average Ag–S bond length in 4 is 2.6802(6) Å, which
are comparable to those in related bimetallic complexes
such as [(PPh3)2Cu(SEt)2In(SEt)2] (av. Cu–S = 2.418(2) Å) [15] and
[(PPh3)2Ag(SMe)2In(SMe)2] (av. Ag–S = 2.6797(10) Å) [21].
Fig. 3. A perspective view of the structure of [Ga(edt)2Cu(PPh3)2] 3.
Fig. 2. A view of the [Ga(edt)2]ꢀ anion in 2.
Fig. 4. A perspective view of the structure of [Ga(edt)2Ag(PPh3)2] 4.

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Y.-G. Han et al. / Inorganica Chimica Acta 365 (2011) 414–418
coordinate with [M(PPh3)2]+ species, resulting in heterobimetallic
complexes [Ga(edt)2M(PPh3)2] (M = Cu, Ag). The potential applica-
tion of such complexes as single-source precursors for ternary sul-
fide materials was investigated by thermogravimetry analysis.
Table 3
Selected bond distances (Å) and bond angles (°) for 2, 3 and 4.
2
3a (M = Cu)
3b (M = Cu)
4 (M = Ag)
Ga(1)–S(1)
Ga(1)–S(2)
Ga(1)–S(3)
Ga(1)–S(4)
M(1)–S(1)
M(1)–S(3)
M(1)–P(1)
M(1)–P(2)
Ga(1)ꢁ ꢁ ꢁM(1)
S(1)–Ga(1)–S(2)
S(1)–Ga(1)–S(3)
S(1)–Ga(1)–S(4)
S(2)–Ga(1)–S(3)
S(2)–Ga(1)–S(4)
S(3)–Ga(1)–S(4)
S(1)–M(1)–S(3)
P(1)–M(1)–S(1)
P(2)–M(1)–S(1)
P(1)–M(1)–S(3)
P(2)–M(1)–S(3)
P(1)–M(1)–P(2)
Ga(1)–S(1)–M(1)
Ga(1)–S(3)–M(1)
2.2525(9)
2.2618(8)
2.2711(8)
2.2594(9)
2.3050(6)
2.2227(7)
2.2976(6)
2.2452(7)
2.4047(6)
2.4885(7)
2.2800(6)
2.2842(7)
2.3235(6)
2.2298(7)
2.2998(6)
2.2344(7)
2.4230(6)
2.4764(6)
2.2944(6)
2.2776(6)
2.9892(4)
97.19(3)
106.33(2)
115.73(3)
116.76(3)
123.61(3)
97.08(2)
2.2951(6)
2.2410(7)
2.3175(7)
2.2338(7)
2.7204(6)
2.6399(6)
2.4622(6)
2.4818(6)
Acknowledgements
This project was supported by the Natural Science Foundation
of China (20871002) and the Program for New Century Excellent
Talents in University of China (NCET-08-0618).
96.52(4)
115.93(4)
115.66(4)
116.49(4)
117.23(4)
96.44(3)
97.59(3)
104.08(2)
119.10(3)
118.82(3)
120.46(3)
96.96(3)
95.72(2)
114.42(2)
109.86(2)
108.37(2)
106.60(2)
118.98(2)
80.88(2)
79.24(2)
96.56(3)
110.70(2)
114.10(3)
114.02(3)
125.11(3)
96.82(3)
90.11(2)
109.37(2)
104.53(2)
116.99(2)
115.10(2)
116.30(2)
78.87(2)
80.20(2)
Appendix A. Supplementary material
CCDC 731839, 731840, and 731841 contain the supplementary
crystallographic data for this paper. These data can be obtained
free of charge from The Cambridge Crystallographic Data Centre
via www.ccdc.cam.ac.uk/data_request/cif.
Supplementary data associated with this article can be found, in
the online version, at doi:10.1016/j.ica.2010.09.044.
98.09(2)
113.41(2)
113.08(2)
105.30(2)
109.09(2)
115.89(2)
78.04(2)
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77.39(2)
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in a relatively high yield which could be used as a metalloligand to