Octahedral cyanohydroxo cluster complex trans-[Re_6Se _8(CN)_4(OH)_2]~(4-): Synthesis, crystal structure, and properties

摘要

A hexarhenium cyanohydroxo anionic cluster complex [Re_6Se _8(CN)_4(OH)_2]~(4-) was synthesized for the first time starting from [Re_6Se_8(OH)_6] ~(4-), which was crystallized as a salt of the composition Cs _(2.75)K_(1.25)[Re_6Se_8(CN) _4(OH)_2]·H_2O (1). The reaction of the complex with Cu~(2+) in an aqueous ammonia or methylamine solutions afforded [Cu(NH_3)_5]_2[Re_6Se _8(CN)_4(OH)_2]·8H_2O (2) or [{Cu(CH_3NH_2)_4}2Re_6Se _8(CN)_4(OH)_2] (3), respectively. All of these three compounds were characterized by a single-crystal X-ray diffraction method. Compound 1 is crystallized in the tetragonal space group I4/m with eight formula units per cell (a = b = 17.4823(14), c = 19.430(2), V = 5938.3(10) ~3); compound 2 is crystallized in the monoclinic space group P2 _1 with two formula units per cell (a = 12.1845(13), b = 8.6554(9), c = 19.2568(19), β = 91.081(2)°, V = 2030.5(4) ~3); compound 3 is crystallized in the orthorhombic space group Cmcm with four formula units per cell (a = 19.816(4), b = 14.611(3), c = 13.751(3), V = 3981.2(13) ~3). The luminescence properties of 1 were studied in both aqueous solution and solid state. In addition, the electronic structure of [Re_6Se_8(CN)_4(OH)_2]~(4-) was elucidated by DFT calculations.