LN(3)CU(4)P(4)O(2) - A NEW LANTHANIDE TRANSITION-METAL PNICTIDE OXIDESTRUCTURE TYPE

A new type of lanthanide transition metal pnictide oxide, Ln(3)Cu(4)P( 4)O(2) (for Ln = La, Ce, and Nd), is reported. The crystal structure i s made from Ln(2)O(2) layers of the Pb2O2 type stacked with layers of Cu2P2 tetrahedra and indicates the existence of a homologous series of compounds with similar chemistry connecting the BiCuOSe and ThCr2Si2 structure types. The resistivity of La3Cu4P4O2 is metallic, with no su perconductivity observed above 2 K. The Ce and Nd compounds have magne tic susceptibilities characteristic of the trivalent Lanthanides. No m agnetic ordering is observed above 4.2 K. (C) 1997 Academic Press.