Eur. Phys. J. B (2013) 86: 369
https://doi.org/10.1140/epjb/e2013-40415-6

Regular Article

Chemical and physical insight on the local properties of the phosphides XSiP₂ (X = Be, Mg, Cd, Zn and Hg) under pressure: from first principles calculations

¹ Laboratoire de Physique Théorique, Université de Tlemcen, 13000 Tlemcen, Algeria
² École Préparatoire en Sciences et Techniques, BP 165 R.P., 13000 Tlemcen, Algeria

^a e-mail: tarikouahrani@yahoo.fr

Received: 19 April 2013
Received in final form: 18 June 2013
Published online: 2 September 2013

Abstract

Local properties of the XSiP₂ (X = Be, Mg, Cd, Zn and Hg) compounds are revisited through the partition of static thermodynamic properties under pressure. We pay attention to the metallization that occurs when the investigated compounds undergo a phase transition from chalcopyrite to the NaCl structure. Electron localization function analysis shows that the local valence basin attractors values decrease as a function of pressure. As the pressure increases, the tetragonal distortion (c/a) diminishes while the degree of ionicity enhances. In addition, by means of atom in molecule approach, atomic-like local compressibility and pressures are analyzed. We found that the basins volumes of the investigated compounds in the NaCl phase have lower compressibilities than those in the chalcopyrite phase. According to the predicted core-valence basins, the phosphorus cation is found to be the more affected by the hydrostatic pressure.