Pressure Induced Structural Phase Transition and Valence Change

The application of hydrostatic pressure on a solid material has a direct effect on the extra-nuclear electronic states of the constituent atoms in the material. In this work, we have studied the effect of pressure on the various properties of the material, such as structural behavior, crystal lattice behavior, magnetic behaviors of magnetic material and transport behavior like electrical resistivity. We have calculated the Ce valency change in some compounds of cerium monochalcogenides CeX (X=O, S, Se and Te) and cerium monopnictides CeX (X=P, As, Sb and Bi). In doing this task, we have reproduced the reported experimental pressure-volume relationships of the compounds using the Birch equation of state. The corresponding pressure-volume relationships of these compounds for stable trivalent cerium have also been calculated using the same Birch equation. Clear effect of pressure on the cerium valency has been realized for each compound from the present calculation.