The crystal structures of the isostructural title compounds poly[(μbenzene1,4dithiolato)dithallium], Tl_{2}(SC_{6}H_{4}S), and poly[(μbenzene1,4diselenolato)dithallium], Tl_{2}(SeC_{6}H_{4}Se), were solved by simulated annealing from highresolution synchrotron Xray powder diffraction. Rietveld refinements of an initial structure with one formula unit per triclinic cell gave satisfactory agreement with the data, but led to a structure with impossibly close nonbonded contacts. A disordered model was proposed to alleviate this problem, but an alternative supercell structure leads to slightly improved agreement with the data. The isostructural superlattice structures were confirmed for both compounds through additional data collection, with substantially better counting statistics, which revealed the presence of very weak superlattice peaks not previously seen. Overall, each structure contains Tl—S or Tl—Se twodimensional networks, connected by phenylene bridges. The sulfur (or selenium) coordination sphere around each thallium is a highly distorted square pyramid or a `seesaw' shape, depending upon how many Tl—S or Tl—Se interactions are considered to be bonds. In addition, the two compounds contain pairs of Tl^{I} ions that interact through a closedshell `thallophilic' interaction: in the sulfur compound there are two inequivalent pairs of Tl atoms with Tl—Tl distances of 3.49 and 3.58 Å, while in the selenium compound those Tl—Tl interactions are at 3.54 and 3.63 Å.
Supporting information
CCDC references: 849841; 849842
For both compounds, data collection: spec; cell refinement: TOPASAcademic (Coelho, 2007); data reduction: X16C beamline software; program(s) used to solve structure: TOPASAcademic (Coelho, 2007); program(s) used to refine structure: TOPASAcademic (Coelho, 2007); molecular graphics: ORTEP3 for Windows (Farrugia, 1997) and Mercury (Version 2.2; Macrae et al., 2006); software used to prepare material for publication: publCIF (Westrip, 2009).
Crystal data top
Tl2·(SC_{6}H_{2}S)  V = 404.85 (9) Å^{3} 
M_{r} = 549.0  Z = 4 
Triclinic, P1  Synchrotron radiation, λ = 0.698163 Å 
Hall symbol: P1  µ = 37 mm^{−}^{1} 
a = 6.5525 (3) Å  T = 298 K 
b = 6.8444 (3) Å  Particle morphology: fine powder 
c = 9.5265 (2) Å  yellow 
α = 71.798 (2)°  cylinder, 8 × 0.7 mm 
β = 85.988 (2)°  Specimen preparation: Prepared at 298 K and 101.325 kPa, cooled at 0 K min^{−}^{1} 
γ = 89.219 (2)°  
Data collection top
Huber diffractometer  Data collection mode: transmission 
Radiation source: synchrotron, NSLS Beamline X16C  Scan method: step 
Si (111) monochromator  2θ_{min} = 2°, 2θ_{max} = 30°, 2θ_{step} = 0.005° 
Specimen mounting: Sample was mounted in a thin walled glass capillary of nominal diameter 0.7 mm.  
Refinement top
R_{p} = 0.070  57 parameters 
R_{wp} = 0.080  0 restraints 
R_{exp} = 0.065  Hatom parameters not refined 
R_{Bragg} = 0.019  Weighting scheme based on measured s.u.'s 
χ^{2} = 1.484  (Δ/σ)_{max} = 0.0001 
5601 data points  Background function: Chebyshev polynomial with 8 coeffecients plus 1/(2theta) term 
Excluded region(s): none  Preferred orientation correction: none 
Profile function: Simple_Axial_Model(width parameter 8.80/300) function with Rp=9999,Rs=300
in TOPASAcademic  
Crystal data top
Tl2·(SC_{6}H_{2}S)  γ = 89.219 (2)° 
M_{r} = 549.0  V = 404.85 (9) Å^{3} 
Triclinic, P1  Z = 4 
a = 6.5525 (3) Å  Synchrotron radiation, λ = 0.698163 Å 
b = 6.8444 (3) Å  µ = 37 mm^{−}^{1} 
c = 9.5265 (2) Å  T = 298 K 
α = 71.798 (2)°  cylinder, 8 × 0.7 mm 
β = 85.988 (2)°  
Data collection top
Huber diffractometer  Scan method: step 
Specimen mounting: Sample was mounted in a thin walled glass capillary of nominal diameter 0.7 mm.  2θ_{min} = 2°, 2θ_{max} = 30°, 2θ_{step} = 0.005° 
Data collection mode: transmission  
Refinement top
R_{p} = 0.070  5601 data points 
R_{wp} = 0.080  57 parameters 
R_{exp} = 0.065  0 restraints 
R_{Bragg} = 0.019  Hatom parameters not refined 
χ^{2} = 1.484  
Special details top
Experimental. In order to decrease sample absorption, the sample was mixed with finely ground cork before loading into the capillary. This diluted the sample to prevent absorption corrections as well as ensuring no preferred orientation. 
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All suś are estimated from the variances of the (full) variancecovariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles 
Refinement. The two S(C6H4)S moieties were refined as zmatrices, with planar regula hexagonal symmetry imposed for the aromatic rings, located at inversion centers. SC bond lengths were refined, but S atoms were fixed in the planes of the hexagons, with SC—C bond angles fixed at 60 °. 
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å^{2}) top  x  y  z  U_{iso}*/U_{eq}  
Tl2  0.0132 (4)  0.6150 (6)  0.6442 (4)  0.0385 (7)*  
S1  0.05050  0.06291  −0.34303  0.006 (3)*  
C1  0.02217  0.02761  −0.15058  0.006 (3)*  
C2  −0.11884  0.14282  −0.09585  0.006 (3)*  
C3  −0.14101  0.11521  0.05473  0.006 (3)*  
Tl1  0.4572 (4)  0.8920 (6)  0.3612 (3)  0.0385 (7)*  
S1A  0.53129  0.52569  −0.33719  0.006 (3)*  
C1A  0.51373  0.51128  −0.14802  0.006 (3)*  
C2A  0.35925  0.39595  −0.05277  0.006 (3)*  
C3A  0.34552  0.38467  0.09525  0.006 (3)*  
H2  −0.21154  0.25423  −0.17062  0.006 (3)*  
H3  −0.25100  0.20508  0.09742  0.006 (3)*  
H2A  0.24946  0.31479  −0.09393  0.006 (3)*  
H3A  0.22501  0.29471  0.16955  0.006 (3)*  
Geometric parameters (Å, º) top
Tl2—S1^{i}  3.0752  C2—H2  1.0800 
Tl1—S1A^{ii}  2.9379  C3—H3  1.0800 
S1—C1  1.7695  C1A—C2A  1.3845 
S1A—C1A  1.7695  C1A—C3A^{ii}  1.3845 
C1—C3^{iii}  1.3845  C2A—C3A  1.3845 
C1—C2  1.3845  C2A—H2A  1.0800 
C2—C3  1.3845  C3A—H3A  1.0800 
   
Tl1···S1A^{iv}  3.9216  S1···Tl2^{xii}  3.1193 
Tl1···S1^{i}  3.3483  S1···Tl2^{xiii}  3.7477 
Tl1···S1^{ii}  3.2321  S1A···Tl1^{xiii}  3.2309 
Tl1···C2^{i}  3.5408  S1A···Tl2^{xiii}  3.4481 
Tl1···C1^{i}  3.7868  S1A···Tl2^{xiv}  3.2067 
Tl1···C1^{ii}  3.7908  S1A···S1A^{xv}  3.2829 
Tl1···C3^{v}  3.7466  S1A···Tl1^{iv}  3.9216 
Tl1···Tl2  3.897 (4)  C1···Tl1^{ii}  3.7908 
Tl1···S1A^{vi}  3.2309  C1···Tl1^{i}  3.7868 
Tl1···C3A^{vii}  3.6304  C1A···C2^{xvi}  3.4091 
Tl2···Tl1  3.897 (4)  C1A···Tl2^{xiv}  3.6622 
Tl2···C2^{vi}  3.4788  C2···C3A^{i}  3.5418 
Tl2···S1^{vi}  3.7477  C2···C1A^{xvii}  3.4091 
Tl2···C2A^{vi}  3.7206  C2···Tl1^{i}  3.5408 
Tl2···S1^{viii}  3.1193  C2···Tl2^{xiii}  3.4788 
Tl2···S1A^{ix}  3.2067  C2A···Tl2^{xiii}  3.7206 
Tl2···S1A^{vi}  3.4481  C3···C3A^{i}  3.5555 
Tl2···C1A^{ix}  3.6622  C3···Tl1^{xviii}  3.7466 
Tl2···C3A^{x}  3.2974  C3A···Tl2^{x}  3.2974 
S1···S1^{xi}  3.4678  C3A···C3^{i}  3.5555 
S1···Tl1^{i}  3.3483  C3A···C2^{i}  3.5418 
S1···Tl1^{ii}  3.2321  C3A···Tl1^{xix}  3.6304 
   
Tl2^{i}—S1—C1  141.47  C1^{iii}—C3—H3  120.00 
Tl1^{ii}—S1A—C1A  109.38  S1A—C1A—C2A  120.00 
S1—C1—C2  120.00  S1A—C1A—C3A^{ii}  120.00 
S1—C1—C3^{iii}  120.00  C2A—C1A—C3A^{ii}  120.00 
C2—C1—C3^{iii}  120.00  C1A—C2A—C3A  120.00 
C1—C2—C3  120.00  C1A^{ii}—C3A—C2A  120.00 
C1^{iii}—C3—C2  120.00  C1A—C2A—H2A  120.00 
C1—C2—H2  120.00  C3A—C2A—H2A  120.00 
C3—C2—H2  120.00  C2A—C3A—H3A  120.00 
C2—C3—H3  120.00  C1A^{ii}—C3A—H3A  120.00 
   
Tl2^{i}—S1—C1—C2  24.88  C2—C1—C3^{iii}—C2^{iii}  0.00 
Tl2^{i}—S1—C1—C3^{iii}  −155.12  C1—C2—C3—C1^{iii}  0.00 
Tl1^{ii}—S1A—C1A—C3A^{ii}  126.01  S1A—C1A—C2A—C3A  180.00 
Tl1^{ii}—S1A—C1A—C2A  −53.99  C3A^{ii}—C1A—C2A—C3A  −0.02 
C3^{iii}—C1—C2—C3  0.00  S1A—C1A—C3A^{ii}—C2A^{ii}  180.00 
S1—C1—C2—C3  179.98  C2A—C1A—C3A^{ii}—C2A^{ii}  0.02 
S1—C1—C3^{iii}—C2^{iii}  −179.98  C1A—C2A—C3A—C1A^{ii}  0.00 
Symmetry codes: (i) −x, −y+1, −z; (ii) −x+1, −y+1, −z; (iii) −x, −y, −z; (iv) −x+1, −y+2, −z; (v) x+1, y+1, z; (vi) x, y, z+1; (vii) x, y+1, z; (viii) x, y+1, z+1; (ix) x−1, y, z+1; (x) −x, −y+1, −z+1; (xi) −x, −y, −z−1; (xii) x, y−1, z−1; (xiii) x, y, z−1; (xiv) x+1, y, z−1; (xv) −x+1, −y+1, −z−1; (xvi) x+1, y, z; (xvii) x−1, y, z; (xviii) x−1, y−1, z; (xix) x, y−1, z. 
Crystal data top
Tl2·(SeC_{6}H_{2}Se)  γ = 88.659 (3)° 
M_{r} = 642.8  V = 426.72 (1) Å^{3} 
Triclinic, P1  Z = 4 
Hall symbol: P1  Synchrotron radiation, λ = 0.699855 Å 
a = 6.67438 (8) Å  T = 298 K 
b = 6.84998 (8) Å  Particle morphology: fine powder 
c = 9.82649 (10) Å  redorange 
α = 72.513 (2)°  flat sheet, 8 × 17 mm 
β = 84.790 (2)°  Specimen preparation: Prepared at 298 K and 101.325 kPa, cooled at 0 K min^{−}^{1} 
Data collection top
Huber diffractometer  Data collection mode: reflection 
Radiation source: synchrotron, NSLS Beamline X16C  Scan method: step 
Si (111) monochromator  2θ_{min} = 3°, 2θ_{max} = 40°, 2θ_{step} = 0.005° 
Specimen mounting: Flat plate geometry on zerobackground holder.  
Refinement top
R_{p} = 0.049  94 parameters 
R_{wp} = 0.056  0 restraints 
R_{exp} = 0.020  Hatom parameters not refined 
R_{Bragg} = 0.026  Weighting scheme based on measured s.u.'s 
χ^{2} = 7.756  (Δ/σ)_{max} = 0.0001 
7401 data points  Background function: Chebyshev polynomial with 8 coeffecients plus 1/(2theta) term 
Excluded region(s): none  Preferred orientation correction: MarchDollase parameter 0.797(1) in (001) direction 
Profile function: Simple_Axial_Model(width parameter 6.96/300) function with Rp=9999,Rs=300
in TOPASAcademic  
Crystal data top
Tl2·(SeC_{6}H_{2}Se)  β = 84.790 (2)° 
M_{r} = 642.8  γ = 88.659 (3)° 
Triclinic, P1  V = 426.72 (1) Å^{3} 
a = 6.67438 (8) Å  Z = 4 
b = 6.84998 (8) Å  Synchrotron radiation, λ = 0.699855 Å 
c = 9.82649 (10) Å  T = 298 K 
α = 72.513 (2)°  flat sheet, 8 × 17 mm 
Data collection top
Huber diffractometer  Scan method: step 
Specimen mounting: Flat plate geometry on zerobackground holder.  2θ_{min} = 3°, 2θ_{max} = 40°, 2θ_{step} = 0.005° 
Data collection mode: reflection  
Refinement top
R_{p} = 0.049  7401 data points 
R_{wp} = 0.056  94 parameters 
R_{exp} = 0.020  0 restraints 
R_{Bragg} = 0.026  Hatom parameters not refined 
χ^{2} = 7.756  
Special details top
Experimental. In order to decrease sample absorption, the sample was mixed with finely ground cork before loading into the capillary. This diluted the sample to prevent absorption corrections as well as ensuring no preferred orientation. 
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All suś are estimated from the variances of the (full) variancecovariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles 
Refinement. The two Se(C6H4)Se moieties were refined as zmatrices, with planar regula hexagonal symmetry imposed for the aromatic rings, located at inversion centers. Se—C bond lengths were refined, but Se atoms were fixed in the planes of the hexagons, with Se—C—C bond angles fixed at 60 °. 
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å^{2}) top  x  y  z  U_{iso}*/U_{eq}  
Tl1  0.4477 (3)  0.9039 (3)  0.3539 (2)  0.0500*  
Tl2  0.0419 (3)  0.5890 (3)  0.6465 (2)  0.0500*  
Se1  0.06968  0.05017  −0.34935  0.0015 (7)*  
Se1A  0.54913  0.55701  −0.35070  0.0015 (7)*  
C1  0.03022  0.02176  −0.15151  0.0015 (7)*  
C1A  0.52131  0.52473  −0.15209  0.0015 (7)*  
C2  0.15899  −0.11212  −0.05330  0.0015 (7)*  
C2A  0.38131  0.37526  −0.05822  0.0015 (7)*  
C3  0.12877  −0.13388  0.09821  0.0015 (7)*  
C3A  0.36000  0.35053  0.09387  0.0015 (7)*  
H2  0.27768  −0.19582  −0.09309  0.0015 (7)*  
H2A  0.29270  0.28213  −0.10169  0.0015 (7)*  
H3  0.22490  −0.23382  0.17152  0.0015 (7)*  
H3A  0.25548  0.23894  0.16394  0.0015 (7)*  
Geometric parameters (Å, º) top
Tl1—Se1^{i}  3.2388  C1A—C3A^{i}  1.4467 
Tl1—Se1A^{i}  3.1664  C2—C3  1.4467 
Tl2—Se1^{ii}  3.1815  C2A—C3A  1.4467 
Se1—C1  1.8891  C2—H2  1.0800 
Se1A—C1A  1.8891  C2A—H2A  1.0800 
C1—C2  1.4467  C3—H3  1.0800 
C1—C3^{iii}  1.4467  C3A—H3A  1.0800 
C1A—C2A  1.4467   
   
Tl1···Tl2  3.923 (3)  Se1···Tl1^{vii}  3.4633 
Tl1···Se1^{ii}  4.0217  Se1···Tl2^{vii}  3.3408 
Tl1···Se1A^{iv}  3.2660  Se1···Se1^{xiii}  3.4433 
Tl1···C3^{v}  3.5070  Se1A···Tl2^{xiv}  3.2984 
Tl1···C3A^{v}  3.4237  Se1A···Tl1^{xii}  3.2660 
Tl1···Se1A^{vi}  3.6839  Se1A···Tl2^{xii}  3.3895 
Tl1···C1^{vii}  3.8545  Se1A···Tl1^{vi}  3.6839 
Tl1···Se1^{vii}  3.4633  Se1A···Se1A^{xv}  3.3765 
Tl1···C1A^{vi}  3.8201  C1···Tl2^{xii}  3.7940 
Tl2···Se1^{vii}  3.3408  C1···Tl1^{vii}  3.8545 
Tl2···C3^{viii}  3.5010  C1···C3A^{iii}  3.5752 
Tl2···C2A^{iv}  3.7656  C1A···C3^{xvi}  3.4616 
Tl2···Tl1  3.923 (3)  C1A···Tl1^{vi}  3.8201 
Tl2···Se1^{iv}  3.6794  C1A···Tl2^{xiv}  3.8056 
Tl2···Se1A^{ix}  3.2984  C2A···Tl2^{xii}  3.7656 
Tl2···Se1A^{iv}  3.3895  C3···Tl1^{xvii}  3.5070 
Tl2···C1^{iv}  3.7940  C3···Tl2^{viii}  3.5010 
Tl2···C1A^{ix}  3.8056  C3···C1A^{xvi}  3.4616 
Tl2···C3A^{x}  3.6354  C3A···Tl2^{x}  3.6354 
Se1···Tl1^{xi}  4.0217  C3A···C1^{iii}  3.5752 
Se1···Tl2^{xii}  3.6794  C3A···Tl1^{xvii}  3.4237 
   
Se1^{i}—Tl1—Se1A^{i}  96.33  C1A—C2A—C3A  120.00 
Tl2^{xi}—Se1—C1  102.20  C1^{iii}—C3—C2  120.00 
Tl1^{i}—Se1—C1  92.41  C1A^{i}—C3A—C2A  120.00 
Tl1^{i}—Se1—Tl2^{xi}  100.07  C1—C2—H2  120.00 
Tl1^{i}—Se1A—C1A  101.56  C3—C2—H2  120.00 
Se1—C1—C2  120.00  C1A—C2A—H2A  120.00 
Se1—C1—C3^{iii}  120.00  C3A—C2A—H2A  120.00 
C2—C1—C3^{iii}  120.00  C2—C3—H3  120.00 
Se1A—C1A—C2A  120.00  C1^{iii}—C3—H3  120.00 
Se1A—C1A—C3A^{i}  120.00  C2A—C3A—H3A  120.00 
C2A—C1A—C3A^{i}  120.00  C1A^{i}—C3A—H3A  120.00 
C1—C2—C3  120.00   
   
Tl2^{xi}—Se1—C1—C2  55.60  Se1—C1—C3^{iii}—C2^{iii}  −180.00 
Tl2^{xi}—Se1—C1—C3^{iii}  −124.40  C2—C1—C3^{iii}—C2^{iii}  0.00 
Tl1^{i}—Se1—C1—C2  −45.24  Se1A—C1A—C2A—C3A  180.00 
Tl1^{i}—Se1—C1—C3^{iii}  134.76  C3A^{i}—C1A—C2A—C3A  0.00 
Tl1^{i}—Se1A—C1A—C2A  −42.83  Se1A—C1A—C3A^{i}—C2A^{i}  180.00 
Tl1^{i}—Se1A—C1A—C3A^{i}  137.17  C2A—C1A—C3A^{i}—C2A^{i}  0.00 
Se1—C1—C2—C3  180.00  C1—C2—C3—C1^{iii}  0.00 
C3^{iii}—C1—C2—C3  0.00  C1A—C2A—C3A—C1A^{i}  0.02 
Symmetry codes: (i) −x+1, −y+1, −z; (ii) x, y+1, z+1; (iii) −x, −y, −z; (iv) x, y, z+1; (v) x, y+1, z; (vi) −x+1, −y+2, −z; (vii) −x, −y+1, −z; (viii) −x, −y, −z+1; (ix) x−1, y, z+1; (x) −x, −y+1, −z+1; (xi) x, y−1, z−1; (xii) x, y, z−1; (xiii) −x, −y, −z−1; (xiv) x+1, y, z−1; (xv) −x+1, −y+1, −z−1; (xvi) −x+1, −y, −z; (xvii) x, y−1, z. 
Experimental details
 (Tl2SC6H4S)  (Tl2SeC6H4Se) 
Crystal data 
Chemical formula  Tl2·(SC_{6}H_{2}S)  Tl2·(SeC_{6}H_{2}Se) 
M_{r}  549.0  642.8 
Crystal system, space group  Triclinic, P1  Triclinic, P1 
Temperature (K)  298  298 
a, b, c (Å)  6.5525 (3), 6.8444 (3), 9.5265 (2)  6.67438 (8), 6.84998 (8), 9.82649 (10) 
α, β, γ (°)  71.798 (2), 85.988 (2), 89.219 (2)  72.513 (2), 84.790 (2), 88.659 (3) 
V (Å^{3})  404.85 (9)  426.72 (1) 
Z  4  4 
Radiation type  Synchrotron, λ = 0.698163 Å  Synchrotron, λ = 0.699855 Å 
µ (mm^{−}^{1})  37  – 
Specimen shape, size (mm)  Cylinder, 8 × 0.7  Flat sheet, 8 × 17 

Data collection 
Diffractometer  Huber diffractometer  Huber diffractometer 
Specimen mounting  Sample was mounted in a thin walled glass capillary of nominal diameter 0.7 mm.  Flat plate geometry on zerobackground holder. 
Data collection mode  Transmission  Reflection 
Scan method  Step  Step 
2θ values (°)  2θ_{min} = 2 2θ_{max} = 30 2θ_{step} = 0.005  2θ_{min} = 3 2θ_{max} = 40 2θ_{step} = 0.005 

Refinement 
R factors and goodness of fit  R_{p} = 0.070, R_{wp} = 0.080, R_{exp} = 0.065, R_{Bragg} = 0.019, χ^{2} = 1.484  R_{p} = 0.049, R_{wp} = 0.056, R_{exp} = 0.020, R_{Bragg} = 0.026, χ^{2} = 7.756 
No. of data points  5601  7401 
No. of parameters  57  94 
Hatom treatment  Hatom parameters not refined  Hatom parameters not refined 
Selected geometric parameters (Å, º) for (Tl2SC6H4S) topTl2—S1^{i}  3.0752  S1—C1  1.7695 
Tl1—S1A^{ii}  2.9379  S1A—C1A  1.7695 
   
Tl2^{i}—S1—C1  141.47  S1—C1—C3^{iii}  120.00 
Tl1^{ii}—S1A—C1A  109.38  S1A—C1A—C2A  120.00 
S1—C1—C2  120.00  S1A—C1A—C3A^{ii}  120.00 
Symmetry codes: (i) −x, −y+1, −z; (ii) −x+1, −y+1, −z; (iii) −x, −y, −z. 
Selected geometric parameters (Å, º) for (Tl2SeC6H4Se) topTl1—Se1^{i}  3.2388  Se1—C1  1.8891 
Tl1—Se1A^{i}  3.1664  Se1A—C1A  1.8891 
Tl2—Se1^{ii}  3.1815   
   
Se1^{i}—Tl1—Se1A^{i}  96.33  Se1—C1—C2  120.00 
Tl2^{iii}—Se1—C1  102.20  Se1—C1—C3^{iv}  120.00 
Tl1^{i}—Se1—C1  92.41  Se1A—C1A—C2A  120.00 
Tl1^{i}—Se1—Tl2^{iii}  100.07  Se1A—C1A—C3A^{i}  120.00 
Tl1^{i}—Se1A—C1A  101.56   
Symmetry codes: (i) −x+1, −y+1, −z; (ii) x, y+1, z+1; (iii) x, y−1, z−1; (iv) −x, −y, −z. 