A new mixed group 5 metal selenide, Nb1.41V0.59Se9

作者：Lee Eunsil; Yun Hoseop^*

来源：Acta Crystallographica Section E-Structure Reports Online, 2011, 67: I50-U167.

DOI：10.1107/S1600536811033319

The new mixed-metallic phase, niobium vanadium nonaselenide, (Nb2-xVx)Se-9 (0.18 <= x <= 0.59) is isostructural with monoclinic V2Se9. The structure is composed of chains of bicapped trigonal-prismatic [MSe8] units. The metal (M) site is occupied by statistically disordered Nb [0.706 (5)] and V [0.294 (5)] atoms. Two trigonal prisms are linked by sharing a rectangular face composed of two Se-2(2-) pairs. Through three edging and capping Se atoms, the chains are extended along [101]. The chain shows alternating short [2.8847 (7) angstrom] and long [3.7159 (7) angstrom] M-M distances. The structure shows a wide range of Se-Se interactions. In addition to the Se-2(2-) pairs of the rectangular face, an intermediate Se center dot center dot center dot Se separation [2.6584 (5) angstrom] is found. The amount of each metal can vary, [(Nb2-xVx)Se-9, 0.18 <= x <= m 0.59] and they seem to form a random substitutional solid solution. The M-M distances increase gradually by increasing the amount of Nb atoms. The classical charge-balance of the compound can be described as [M4+](2)[Se-2(2-)](2)[Se-5(4-)].

• 出版日期2011-9