Cluster ab initio calculations of the shape of local potential well and of positions for oxygen atoms in PCN (C=Cd)

Karadag F., Palaz S., Gungor S., Mamedov A., Kvyatkovskii O. E.

FERROELECTRICS, vol.283, pp.61-66, 2003 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 283
  • Publication Date: 2003
  • Doi Number: 10.1080/00150190390204132
  • Journal Name: FERROELECTRICS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.61-66
  • Çukurova University Affiliated: Yes

Abstract

Potential relief and equilibrium positions for oxygen atoms in Cd-O-Nb, Cd-O-Cd and Nb-O-Nb chains are studied in Pb(Cd1/3Nb2/3)O-3 (PCN) and Ba(Cd1/3Nb2/3)O-3 (BCN). Total energy cluster calculations are performed using ab initio restricted Hartree-Fock method. The electron correlation contribution is calculated within Moller-Plesset method. It is revealed that in PCN the oxygen atoms in Cd-O-Cd and Cd-O-Nb chains move in multi-well potentials with four minima shifted transversely to fourfold [001] axis. Whereas the oxygen atom in Nb-O-Nb chain in PCN and all oxygen atoms in BCN move in single-well potentials.