High-pressure Raman study of SrMoO₄ up to 37 GPa and pressure-induced phase transitions

Abstract

Pressure-induced phase changes in SrMoO₄ were investigated by high-pressure Raman spectroscopy in a diamond anvil cell. The scheelite-type SrMoO₄ transforms in to a monoclinic lattice near 13 GPa and retains this structure up to 37 GPa, the limit of pressure tested. There is no pressure-induced amorphization in this simple molybdate up to this pressure, as in the case of structurally complex molybdate systems. The optical absorption characteristics of SrMoO₄ change considerably with pressure, the sample turning progressively deep orange-brown with increase in pressure. This change is connected with the lowering of the d-state of molybdenum in the MoO₄ ion with increase in pressure.