Elastic Constants of RbF from 300 to 4.2 K

Abstract

The adiabatic elastic constants have been measured in single crystals of rubidium fluoride over the temperature range of 300 to 4.2 K to investigate a discrepancy with neutron scattering data. The values of the elastic constants at 0 K, extrapolated from 4.2 K, are ${C}_{11}=6.527$, ${C}_{44}=0.952$, and ${C}_{12}=1.255$ in units of ${10}^{11}$ ${\mathrm{d}\mathrm{y}\mathrm{n}/\mathrm{c}\mathrm{m}}^{2}$. The Debye characteristic temperature at 0 K (${\ensuremath{\Theta}}_{D}$) as calculated from the elastic constants is ${\ensuremath{\Theta}}_{D}=221.0$ K. A summary of Debye temperature values calculated from elastic constant data at 0 K is presented for all previously measured face-centered-cubic alkali halides.