Inelastic X-ray scattering of RTAl3 (R = La, Ce, T = Cu, Au)

Abstract Inelastic X-ray scattering (IXS) experiments of RT Al 3 ( R = La Ce, T = Cu, Au) were carried out at 300 and 5.5 K. The spectra between LaCuAl 3 and CeCuAl 3 (LaAuAl 3 and CeAuAl 3 ) are nearly identical at both temperatures except for temperature factors such as temperature dependence of Bose factor in IXS spectra and effect on thermal expansion. This means that no evident temperature dependence of IXS spectra was observed in Ce T Al 3 ( T = Cu, Au). Since the major contribution of scattering cross section in IXS measurements is Thomson scattering, the present results failed to confirm the presence of vibron in these compounds.