A molybdenyl chloromonophosphate with an intersecting tunnel structure: Ba3Li2Cl2(MoO)(4)(PO4)(6)

摘要

A new molybdenyl chloromonophosphate, Ba3Li2Cl2(MoO)(4) (PO4)(6), has been synthesized. It crystallizes in the space group P2(1)2(1)2(1), with a = 9.1768(4), b = 15.660(1), and r = 18.117(2) Angstrom. This original pseudotetragonal structure forms an intersecting tunnel framework [Mo4P6O28](infinity) built up from [Mo2P2O12](infinity) layers interconnected through single PO4 tetrahedra. The [Mo2P2O12](infinity) layers derive from the perovskite structure by replacing one octahedron out of two by one PO4 tetrahedron. The Li+, Ba2+, and Cl- species are distributed in the [100], [001], [201], and [20 (1) over bar] tunnels forming intersecting rows. Two sorts of polyhedra are found for Li+: LiO3Cl tetrahedra and LiO3 triangular groups. The susceptibility measurements suggest a bidimensional antiferromagnetic behavior between 12 and 20 K, whereas a peak at 10 K is attributed to canting phenomena, (C) 1998 Academic Press. [References: 9]