Thermal Shifts in Energy Level Separations in Some Rubidium and Silver Halides Studied by ESCA

Abstract
Energy level separations and their temperature dependences have been measured for some rubidium and silver halides. The observed thermal shifts agree quite well with the shifts in Madelung energy due to thermal expansion for the outer levels in the rubidium halides and the core levels in RbCl and AgCl. The experimental results on the bromides, however, indicate that differences in repulsive effects between different core levels are significant. The phase transition in AgI at 147°C is shown to influence the energy separation between the Ag 3d and I 3d levels. Valence band results for the silver halides at different temperatures are presented.