Synthesis and structure of Nb 2( μ2- Se2) 2( Te2I6) 2

Abstract

Compound Nb 2(μ 2-Se 2) 2(Te 2I 6) 2 was obtained in high yield by high-temperatuire reaction (500°C) of the dinuclear cluster complex Nb 2(μ 2-Se 2) 2I 4 with thermal Te and I 2 in a 1:4:4: ratio. The structure of Nb 2Se 4Te 4I 12 has been determined by single-crystal X-ray diffraction. It is characterized by the presence of isolated molecules of [Nb 2(μ 2-Se 2) 2(Te 2I 6) 2]. The ineer skeleton is formed by a dinuclear [Nb 2(μ 2-Se 2) 2] 4+ fragment with a NbNb distance of 2.926(2) Å; the SeSe distances are 2.310(2) and 2.311(2) Å. Each Nb atom is ligated (formally) by Te 2I 6 2− ligands. The terminal TeI distances in the Te 2I 6 2− ligands range from 2.735(2) to 2.786(2) Å. The bridging TeI distances are rather long, ranging from 3.175(1) to 3.261(2) Å.