A time-of-flight neutron diffraction study of anharmonic thermal vibrations in SrF₂, at the spallation neutron source ISIS

Measurements have been made, at wavelengths in the range 0.3-6.2 Å, of hhl reflections of SrF₂ on the single-crystal diffractometer (SXD) at the ISIS Spallation Neutron Source. After application of a variable-wavelength extinction correction to the derived |F_hkl| values, a refinement of the anharmonicity parameter β_F of the fluorine atoms was carried out, yielding a value of -4.19 (30) × 10^-19 J Å^-3.