PREPARATION STRUCTURE AND PHYSICAL-PROPERTIES OF NEW SILVER LANTHANIDE MOLYBDENUM OXIDES [AGLNMO(2)O(8)(LN=LA-ND AND SM)]

We present the synthesis of AgLnMo(2)O(8) compounds with Ln = La-Nd an d Sm. These compounds represent a scheelite-type structure characteriz ed by MoO4- tetrahedrons. IR spectra show five absorption peaks in the region of 1000-400cm(-1), around 800cm(-1) and 400cm(-1), which corre spond to the modes of the tetrahedral MoO42- groups. All of AgLnMo(2)O (8) (Ln = La-Nd and Sm) oxides are dielectric materials at room temper ature. The temperature dependence of the magnetic susceptibility ofAgL nMo(2)O(8) (Ln = Ce-Nd and Sm) shows Curie-Weiss law behavior from 100 K to 300K. This indicates that both Ce and Pr exist in +3 oxidation st ate in AgLnMo(2)O(8). For AgLaMo2O8, diamagnetic properties are found as expected.