Pressure Dependence of the TA[100] Zone-Boundary Phonon Frequency in Rubidium Iodide

Abstract

The frequency of the TA[100] zone-boundary phonon has been measured in rubidium iodide under hydrostatic pressures of 0 to 3.72 kbar by neutron inelastic scattering. A linear fit to the percentage decrease in frequency gives a value of 13.5±0.9% when extrapolated to the NaCl-CsCl polymorphic transition pressure.