Cluster ab initio modeling of local lattice instability in relaxor ferroelectrics


KVYATKOVSKII O., Karadag F. , MAMEDOV A., ZAKHAROV G.

PHYSICS OF THE SOLID STATE, cilt.46, ss.1717-1721, 2004 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 46 Konu: 9
  • Basım Tarihi: 2004
  • Doi Numarası: 10.1134/1.1799192
  • Dergi Adı: PHYSICS OF THE SOLID STATE
  • Sayfa Sayısı: ss.1717-1721

Özet

The possibility of a zigzag-type instability occurring for oxygen atoms in B-O-B, B-O-Nb, and Nb-O-Nb linear chains is examined in disordered mixed perovskite compounds Pb(B-1/3, Nb-2/3)O-3 (B = Mg, Zn. Cd). Local adiabatic potentials for oxygen atoms are studied using total energy calculations by the ab initio Hartree-Fock + MP2 method for many-atomic clusters with different oxygen surroundings of lead atoms. The effect of lattice relaxation along the chain on the shape of the local potential in the transverse direction for the central oxygen atom is considered. (C) 2004 MAIK "Nauka/Interperiodica".