High-pressure synthesis and structure of the new niobium phosphide Nb₂P₅

Abstract

Nb2P 5 was prepared by reaction of the elements at 3-5 GPa and 1273 K using a cubic-anvil-type apparatus. The crystal is orthorhombic, Pnma, with a = 16.742 (3), b = 3.3499 (6), c = 7.912 (1) A, Z = 4, and D x = 5.10 Mg m -a. The structure was refined to R = 0.037 for 1198 independent reflections. The structure of Nb2P 5 is closely related to the OsGe2-type structure. Zigzag P~ chains are additionally inserted along the b axis between the Os2Ge 4 rhombic prisms of the OsGe2-type structure. Nb2P s is a metallic conductor and shows Pauli paramagnetism.