Isomeric Molecular Forms of Pseudo-Binuclear Bismuth(III) Dithiocarbamate [Bi2{S2CN(CH2)6}6]: Preparation, Thermal Behavior, and Structural Effect of Its Solvation with DMSO, [Bi2{S2CN(CH2)6}6]⋅2(CH3)2SO

Bismuth(III) hexamethylenedithiocarbamate (HmDtc) [Bi-2{S2CN(CH2)(6)}(6)] (I) and its solvated with dimethyl sulfoxide form [Bi-2(S(2)CNHm)(6)]& sdot;2(CH3)(2)SO (II) have been obtained. The crystal structure of compound I shows an unusual alternation of two unsymmetrical isomeric pseudo-binuclear [Bi-1/1B(HmDtc)(3)<middle dot><middle dot><middle dot>Bi-1A/1C(HmDtc)(3)] molecules, each of which involves two non-equivalent mononuclear moieties combined by secondary Bi<middle dot><middle dot><middle dot>S bonds. The solvation of complex I leads to the structural unification of isomeric [Bi(HmDtc)(3)] molecules followed by their self-organization into centrosymmetric pseudo-dimers in the structure of compound II. All HmDtc ligands coordinate in S,S'-anisobidentate mode to form four isomeric (in I) or structurally unique [Bi(HmDtc)(3)] molecules (in II), whose distorted polyhedra can be approximated by pentagonal pyramid or octahedron. Solvating DMSO molecules are retained in the structure II by C-H<middle dot><middle dot><middle dot>O hydrogen bonds. The analysis of energy dispersive X-ray spectra allowed one to identify the residual matter obtained by thermolysis of the complexes as Bi2S3 with admixture of Bi-0.