Acta Cryst.(2002). E58, m537±m539 DOI: 10.1107/S1600536802015945 Jr and Tiekink [Cd(S2C2H3O)2]
m537
metal-organic papers
Acta Crystallographica Section E Structure Reports Online
ISSN 1600-5368
Bis(
O
-methyldithiocarbonato)cadmium(II)
Victor G. Young Jraand Edward R. T. Tiekinkb*
aDepartment of Chemistry, University of
Minnesota, 160 Kolthoff Hall, 207 Pleasant Street S.E., Minneapolis, MN 55455, USA, and bDepartment of Chemistry, National University
of Singapore, Singapore 117543
Correspondence e-mail: chmtert@nus.edu.sg
Key indicators
Single-crystal synchrotron study
T= 123 K
Mean(O±C) = 0.003 AÊ
Rfactor = 0.030
wRfactor = 0.073
Data-to-parameter ratio = 18.1
For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e.
#2002 International Union of Crystallography Printed in Great Britain ± all rights reserved
To a ®rst approximation, the cadmium centre in the centrosymmetric title compound, [Cd(S2COCH3)2], exists
within anS4donor set which de®nes a distorted square planar
geometry. Molecules associate in the crystal structureviaCdÐ S interactions above and below the square plane, so as to form stacks that might be considered as edge-shared, tetragonally distorted octahedra.
Comment
As highlighted in a bibliographic review of the zinc-triad binary 1,1-dithiolates, e.g. with dithiocarbamate (ÿS
2CNR2),
xanthate (ÿS
2COR), and dithiophosphate [ÿS2P(OR)2] anions,
the structural chemistry of this class of ligands is extra-ordinarily diverse (Cox & Tiekink, 1997). Particularly inter-esting is the observation that very different structural types may be found, even when there has only been a minor change in the nature of the organic substituent. Pertinent to the present paper are the structures of the cadmium bis-(xanthate)s.
The structure of the butylxanthate, i.e. Cd(S2COnBu)2,
features tetrahedral cadmium centres and bridging xanthate ligands, so that a layer structure is formed (Rietveld & Maslen, 1965). A similar motif is found for the ethyl- (Iimura et al., 1972) and isopropylxanthates (Iimura, 1973; Tomlin et al., 1999; Tiekink, 2000). Incredibly, exchanging the-methylene
group in Cd(S2COnBu)2 for an O atom, giving
Cd(S2COCH2CH2OMe)2, leads to an entirely different motif
based on a square planar geometry (Abrahams et al., 1988). The challenge remains to rationalize the diverse structures found in the solid state.
Systematic studies in this ®eld have been hampered by the inability to grow suitable crystals for X-ray analysis. In the case of the title compound, Cd(S2COMe)2, (I), this dif®culty
has been overcome by the utilization of synchrotron radiation, enabling a full structure determination on a microcrystal with dimensions 0.01 0.025 0.025 mm. As described, the structure of (I) resembles that reported earlier for Cd(S2COCH2CH2OMe)2(Abrahamset al., 1988).
The molecular structure of (I) (Fig. 1 & Table 1) is centrosymmetric and features two almost symmetrically chelating xanthate ligands that de®ne anS4donor set leading,
to a ®rst approximation, to a square planar geometry. The
metal-organic papers
m538
Jr and Tiekink [Cd(S2C2H3O)2] Acta Cryst.(2002). E58, m537±m539 variation of the parameters associated with the independentxanthate ligand are as expected; see Table 1. Molecules associate in the crystal structure to form stacks between translationally related molecules aligned along b; one such stack is illustrated in Fig. 2. These are held in place by close Cd S interactions occurring above and below the square plane. The Cd S1i(i:x,yÿ1,z) distance of 2.8881 (6) AÊ is
at least 0.24 AÊ longer than the weaker of the CdÐS bonds de®ning the square plane. The comparable intermolecular CdÐS interaction in the structure of Cd(S2COCH2CH2OMe)2
was reported to be signi®cantly longer at 3.0225 (8) AÊ (Abrahamset al., 1988). If the CdÐS1iinteraction in (I) was
considered signi®cant, the coordination geometry could be considered as tetragonally distorted octahedral and the crystal structure thought of being comprised of edge-shared octa-hedra.
Experimental
Pale-yellow crystals were obtained from the slow evaporation of an acetone solution of the compound, which had been prepared following the literature procedure (Abrahamset al., 1988).
Crystal data
[Cd(C2H3OS2)2]
Mr= 326.73 Monoclinic,C2=c a= 19.006 (2) AÊ b= 3.9728 (3) AÊ c= 12.5126 (14) AÊ
= 107.993 (4)
V= 898.59 (17) AÊ3
Z= 4
Dx= 2.415 Mg mÿ3
Synchrotron radiation
= 0.56357 AÊ
Cell parameters from 2655 re¯ections
= 2.7±21.4 = 1.72 mmÿ1
T= 123 (2) K Plate, yellow
0.0250.0250.01 mm
Data collection
Bruker Mosaic CCD-geometry diffractometer
'scans
Absorption correction: multi-scan (SADABS; Blessing, 1995) Tmin= 0.958,Tmax= 0.998
6696 measured re¯ections
1031 independent re¯ections 992 re¯ections withI> 2(I) Rint= 0.084
max= 21.4
h=ÿ24!23 k= 0!5 l= 0!16
Re®nement
Re®nement onF2
R[F2> 2(F2)] = 0.030
wR(F2) = 0.073
S= 1.01 1031 re¯ections 57 parameters H atoms: see text
w= 1/[2(F
o2) + (0.0667P)2] whereP= (Fo2+ 2Fc2)/3 (/)max< 0.001
max= 0.72 e AÊÿ3
min=ÿ1.22 e AÊÿ3
Extinction correction:SHELXL Extinction coef®cient: 0.0301 (16)
Table 1
Selected geometric parameters (AÊ,).
CdÐS1 2.6364 (6)
CdÐS2 2.6413 (5)
CdÐS1i 2.8881 (6)
S1ÐC1 1.7307 (18)
S2ÐC1 1.6871 (19)
C1ÐO1 1.322 (3)
O1ÐC2 1.454 (3)
S1ÐCdÐS2 69.373 (17) S1ÐCdÐS2ii 110.627 (17)
S2ÐCdÐS1i 90.679 (16)
CdÐS1ÐC1 82.94 (7) CdÐS2ÐC1 83.57 (6)
S1ÐC1ÐO1 113.84 (14) S2ÐC1ÐO1 123.17 (14) S1ÐC1ÐS2 122.99 (11) C1ÐO1ÐC2 118.87 (17)
Symmetry codes: (i)x;yÿ1;z; (ii)1
2ÿx;12ÿy;ÿz.
The H atoms were placed in ideal geometry, with CÐH = 0.98 AÊ, with the aid of a toroidal Fourier synthesis. Re®nement includes one additional parameter for the torsional re®nement of the methyl plus three isotropic displacement parameters for the H atoms. The maximal residual electron density peak was located 0.78 AÊ from the Cd atom
Data collection:SMART-KAPPA(Bruker, 1998); cell re®nement:
SAINT(Bruker, 2000); data reduction:SHELXTL (Bruker, 2000); program(s) used to solve structure: SHELXS86 (Sheldrick, 1986); program(s) used to re®ne structure:SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication:SHELXL97.
The National University of Singapore is thanked for the award of a research grant (R-143-000-151-112). Use of the ChemMatCARS sector 15 at the Advanced Photon Source was supported by the Australian Synchrotron Research Program, which is funded by the Commonwealth of Australia under the Major National Research Facilities Program. Figure 2
View of the molecular aggregation in (I). Figure 1
The molecular structure and crystallographic numbering scheme for (I). Displacement ellipsoids are shown at the 70% probability level (Johnson, 1976). Symmetry operator for generating equivalent atoms:1
2ÿx,12ÿy,
ChemMatCARS Sector 15 is principally supported by the National Science Foundation/Department of Energy under grant number CHE0087817 and by the Illinois Board of Higher Education. The Advanced Photon Source is supported by the US Department of Energy, Basic Energy Sciences, Of®ce of Science, under Contract No. W-31-109-Eng-38. Special thanks go to D. Cookson, T. Graber, and J. Gebhardt at ChemMatCARS, for providing exceptional assistance at 15-ID.
References
Abrahams, B. F., Hoskins, B. F., Tiekink, E. R. T. & Winter, G. (1988).Aust. J. Chem.41, 1117±1122.
Blessing, R. H. (1995).Acta Cryst.A51, 33±38.
Bruker (1998). SMART-KAPPA. (Version V5.A40). Bruker AXS Inc., Madison, Wisconsin, USA.
Bruker (2000).SAINT (Version V6.02A) andSHELXTL(Version V6.12). Bruker AXS Inc., Madison, Wisconsin, USA.
Cox, M. J. & Tiekink, E. R. T. (1997).Rev. Inorg. Chem.17, 1±23. Iimura, Y. (1973).Sci. Pap. Inst. Phys. Chem. Res.(Jpn),67, 43±46. Iimura, Y., Ito, T. & Hagihara, H. (1972).Acta Cryst.B28, 2271±2279. Johnson, C. K. (1976).ORTEPII. Report ORNL-5138, Oak Ridge National
Laboratory, Tennessee, USA.
Rietveld, H. M. & Maslen, E. N. (1965).Acta Cryst.18, 429±436. Sheldrick, G. M. (1986).SHELXS86. University of GoÈttingen, Germany. Sheldrick, G. M. (1997).SHELXL97. University of GoÈttingen, Germany. Tiekink, E. R. T. (2000).Acta Cryst.C56, 1176.
Tomlin, D. W., Cooper, T. M., Zelmon, D. E., Gebeyehu, Z. & Hughes, J. M. (1999).Acta Cryst.C55, 717±719.
Acta Cryst.(2002). E58, m537±m539 Jr and Tiekink [Cd(S2C2H3O)2]
m539
supporting information
sup-1
Acta Cryst. (2002). E58, m537–m539
supporting information
Acta Cryst. (2002). E58, m537–m539 [doi:10.1107/S1600536802015945]
Bis(
O
-methyldithiocarbonato)cadmium(II)
Victor G. Young Jr and Edward R. T. Tiekink
S1. Comment
As highlighted in a bibliographic review of the binary 1,1-dithiolates, e.g. dithiocarbamate (−S
2CNR2), xanthate (−S2COR),
and dithiophosphate (−S
2P(OR)2) anions, the structural chemistry of this class of ligands is extraordinarily diverse (Cox &
Tiekink, 1997). Particularly interesting is the observation that very different structural types may be found even when
there has only been a minor change in the nature of the organic substituent. Pertinent to the present paper are the
structures of the cadmium bis(xanthate)s.
The structure of the butylxanthate, i.e. Cd(S2COnBu)2, features tetrahedral cadmium centres and bridging xanthate
ligands so that a layer structure is formed (Rietveld & Maslen, 1965). A similar motif is found for the ethyl- (Iimura, Ito
& Hagihara, 1972) and isopropyl-xanthates (Iimura, 1973; Tomlin et al., 1999; Tiekink, 2000). Incredibly, exchanging the
γ-methylene group in Cd(S2COnBu)2 for an O atom, giving Cd(S2COCH2CH2OMe)2, leads to an entirely different motif
based on a square planar geometry (Abrahams et al., 1988). The challenge remains to rationalize the diverse structures
found in the solid state.
Systematic studies in this field have been hampered by the inability to grow suitable crystals for X-ray analysis. In the
case of the title compound, Cd(S2COMe)2, (I), this difficulty has been overcome by the utilization of synchrotron
radiation that has enabled a full structure determination on a microcrystal with dimensions 0.01 x 0.025 x 0.025 mm. As
described, the structure of (I) resembles that reported earlier for Cd(S2COCH2CH2OMe)2 (Abrahams et al., 1988).
The molecular structure of (I) (Fig. 1 & Table 1) is centrosymmetric and features two almost symmetrically chelating
xanthate ligands that define an S4 donor set leading, to a first approximation, to a square planar geometry. The variation
of the parameters associated with the independent xanthate ligand are as expected; see Table 1. Molecules associate in the
crystal structure to form stacks between translationally related molecules aligned along b; one such stack is illustrated in
Fig. 2. These are held in place by close Cd···S interactions occurring above and below the square plane. The Cd···S1i (i: x,
y − 1, z) distance of 2.8881 (6) Å is at least 0.24 Å longer than the weaker of the Cd—S bonds defining the square plane.
The comparable intermolecular Cd—S interaction in the structure of Cd(S2COCH2CH2OMe)2 was reported to be
significantly longer at 3.0225 (8) Å (Abrahams et al., 1988). If the Cd—S1i interaction in (I) was considered significant,
the coordination geometry could be considered as tetragoanlly distorted octahedral and the crystal structure thought of
being comprised of edge-shared octahedra.
S2. Experimental
Pale-yellow crystals were obtained from the slow evaporation of an acetone solution of the compound that had been
supporting information
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Acta Cryst. (2002). E58, m537–m539 S3. Refinement
The methyl group was placed torsionally from the Fourier. Isotropic displacement parameters for all three H atoms were
[image:5.610.126.483.123.235.2]refined and the methyl group was allowed to rotate but not to tip.
Figure 1
The molecular structure and crystallographic numbering scheme for (I). Displacement ellipsoids are shown at the 70%
supporting information
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[image:6.610.126.487.72.519.2]Acta Cryst. (2002). E58, m537–m539 Figure 2
View of the molecular aggregation in (I).
(I)
Crystal data
[Cd(S2C2H3O)2] Mr = 326.73
Monoclinic, C2/c Hall symbol: -C 2yc a = 19.006 (2) Å b = 3.9728 (3) Å c = 12.5126 (14) Å β = 107.993 (4)° V = 898.59 (17) Å3 Z = 4
F(000) = 632 Dx = 2.415 Mg m−3
Synchrotron radiation, λ = 0.56357 Å Cell parameters from 2655 reflections θ = 2.7–21.4°
µ = 1.72 mm−1 T = 123 K Plate, yellow
supporting information
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Acta Cryst. (2002). E58, m537–m539 Data collection
Bruker Mosaic KappaCCD diffractometer
Radiation source: APS 15-ID-C synchrotron Silicon monochromator
φ scans
Absorption correction: multi-scan (SADABS; Blessing, 1995) Tmin = 0.958, Tmax = 0.998
6696 measured reflections 1031 independent reflections 992 reflections with I > 2σ(I) Rint = 0.084
θmax = 21.4°, θmin = 1.8° h = −24→23
k = 0→5 l = 0→16
Refinement
Refinement on F2 Least-squares matrix: full R[F2 > 2σ(F2)] = 0.030 wR(F2) = 0.073 S = 1.01 1031 reflections 57 parameters 0 restraints
Primary atom site location: structure-invariant direct methods
Secondary atom site location: difference Fourier map
Hydrogen site location: inferred from neighbouring sites
See experimental section w = 1/[σ2(Fo2) + (0.0667P)2]
where P = (Fo2 + 2Fc2)/3 (Δ/σ)max < 0.001
Δρmax = 0.72 e Å−3 Δρmin = −1.22 e Å−3
Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 Extinction coefficient: 0.0301 (16)
Special details
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)
x y z Uiso*/Ueq
Cd 0.2500 0.2500 0.0000 0.01603 (16)
S1 0.35350 (3) 0.70595 (14) 0.08140 (5) 0.01264 (17)
S2 0.31582 (2) 0.41115 (11) −0.15051 (3) 0.01345 (18)
C1 0.37211 (9) 0.6362 (5) −0.04373 (14) 0.0118 (4)
O1 0.43460 (12) 0.7738 (3) −0.04763 (15) 0.0149 (4)
C2 0.45575 (14) 0.7352 (5) −0.1491 (2) 0.0172 (5)
H2a 0.4582 0.4954 −0.1659 0.021 (6)*
H2b 0.5043 0.8385 −0.1379 0.025 (6)*
H2c 0.4190 0.8459 −0.2120 0.014 (5)*
Atomic displacement parameters (Å2)
U11 U22 U33 U12 U13 U23
Cd 0.0175 (2) 0.0159 (2) 0.0174 (2) −0.00469 (6) 0.00938 (13) −0.00186 (6)
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Acta Cryst. (2002). E58, m537–m539
S2 0.0144 (3) 0.0166 (3) 0.0092 (2) −0.00256 (14) 0.00337 (17) −0.00170 (15)
C1 0.0125 (8) 0.0123 (9) 0.0101 (8) 0.0015 (6) 0.0030 (6) 0.0025 (7)
O1 0.0135 (7) 0.0202 (10) 0.0124 (8) −0.0029 (4) 0.0058 (6) −0.0013 (4)
C2 0.0170 (11) 0.0238 (13) 0.0146 (11) −0.0017 (6) 0.0102 (9) −0.0014 (6)
Geometric parameters (Å, º)
Cd—S1 2.6364 (6) C1—O1 1.322 (3)
Cd—S2 2.6413 (5) O1—C2 1.454 (3)
Cd—S1i 2.8881 (6) C2—H2a 0.9800
S1—C1 1.7307 (18) C2—H2b 0.9800
S2—C1 1.6871 (19) C2—H2c 0.9800
S1—Cd—S2 69.373 (17) S2—C1—O1 123.17 (14)
S1—Cd—S2ii 110.627 (17) S1—C1—S2 122.99 (11)
S1—Cd—S1iii 88.150 (19) C1—O1—C2 118.87 (17)
S2—Cd—S1iii 89.322 (16) O1—C2—H2A 109.5
S2—Cd—S1i 90.679 (16) O1—C2—H2B 109.5
Cd—S1—C1 82.94 (7) H2A—C2—H2B 109.5
Cd—S2—C1 83.57 (6) O1—C2—H2C 109.5
C1—S1—Cdiv 96.20 (6) H2A—C2—H2C 109.5
Cd—S1—Cdiv 91.850 (19) H2B—C2—H2C 109.5
S1—C1—O1 113.84 (14)
