Electron momentum density and phase transition in SrO

Abstract

In this article, we present electron momentum density distribution and phase transition in SrO. The experimental values of momentum density have been measured using 5Ci ²⁴¹Am Compton spectrometer and analyzed using theoretical data obtained from the ab-initio linear combination of atomic orbitals method. The first-principles calculations of the total energy of SrO as a function of cell volume have also been carried out for the cubic rocksalt (B1) and cesium chloride (B2) phases. Several structural parameters, i.e. equilibrium lattice constant, transition pressure, bulk modulus, etc. of B1 and B2 phases have been calculated and compared with the previous investigations. We conclude that the stable phase of SrO is B1 and the phase transition from B1 to B2 occurs at 35.8 GPa.

Keywords:

• SrO
• electron momentum density
• phase transition
• LCAO method

Acknowledgments

This study is financially supported by the University Grant Commission through Emeritus Fellowship F.6-49(SC)/2009 to BKS and research grant SR/39-982/2010 to GS. The financial support provided by DST, New Delhi, is also acknowledged.