CRYSTAL-FIELD SPLITTING IN CEAS UNDER HIGH-PRESSURE

Inelastic neutron scattering measurements have been performed on CeAs under high pressure. The crystal-field splitting Delta(7)(8) and the l ine width of the crystal-field transition Gamma are weakly dependent o n pressure below 2.0 GPa. Above 2.0 GPa, Delta(7)(8) decreases and Gam ma increases rapidly with applied pressure. The line width Gamma at 2. 0 GPa becomes extremely broad with increasing temperature. These resul ts show that above 2.0 GPa p-f mixing effects become strong.