THE MOLYBDENOTUNGSTEN MONOPHOSPHATE MOWO3(PO4)(2) - AN ORIGINAL THREE-DIMENSIONAL FRAMEWORK BUILT UP OF MPO(8) CHAINS (M=MO, W)

摘要

A new molybdenotungsten monophosphate (MoxW2-x)O-3 (PO4)(2) has been synthesized for 0 less than or equal to x less than or equal to 1.25. The crystal structure of the phase MoWO3(PO4)(2) has been determined. This phase crystallizes in the P2(1)/m space group with a = 7.827(1) Angstrom, b = 12.538(1) Angstrom, c = 7.833(1) Angstrom, beta = 92.36(1)degrees. The structure can be described from the assemblage of two kinds of [MPO(8)](infinity) chains running along b, with a cis and trans orientation of the PO4 tetrahedra. Another description which consists of the stacking of two different sorts of [M(2)P(2)O(15)](infinity) layers along b is also presented that involves two sorts of bioctahedral units ''M(2)O(11)'' with the perovskite and HTB configurations, respectively. (C) 1997 Academic Press. [References: 6]