Ionic coordination complexes based on [Re₆S₈(CN)₄L₂]^n– (L = OH^–, NH₃; n = 2, 3) cluster anions, and Ni(II) and Cd(II) ammine cations

Abstract

Two new complexes containing M(II) ammine cations (M = Ni, Cd) and octahedral rhenium(III) thiocyanoammine and thiocyanohydroxoammine cluster anions, [Ni(NH₃)₆][Re₆S₈(CN)₄(NH₃)₂]∙2H₂O (1) and [Cd(NH₃)₆][{Cd(NH₃)₅}{Re₆S₈(CN)₄(OH)(NH₃)}]₂∙5H₂O (2), have been synthesized by hydrothermal reactions starting from Cs_1.83K_2.17[Re₆S₈(CN)₄(OH)₂]∙2H₂O. The compounds were structurally characterized by single-crystal X-ray diffraction analysis, elemental analysis, energy dispersive spectroscopy, and IR spectroscopy. Both compounds adopt monoclinic crystal structures composed from discrete ionic species which are held together by multiple hydrogen bonds between CN^–, OH^–, and NH₃ ligands and lattice water. 2 consists of {Cd(NH₃)₅}²⁺ attached to the OH group of the [Re₆S₈(CN)₄(OH)(NH₃)]^3– cluster anion via the Re–OH–Cd linkage.

Keywords:

• Octahedral rhenium cluster
• Nickel
• Cadmium
• Ammine complex
• Crystal structure

Funding

This research was supported by the Russian Foundation for Basic Research [grant number 11-03-00157], and [grant number 11-03-91052].