Impurity levels and nonlinear optical properties of doped BaTiO3 from extended cluster LDA calculations

1997

The electronic structures of some transition-metal ions doping the ferroelectric oxide BaTiO3 are calculated through the density functional theory framework (LCAO-LSD ADF method) on extended clusters [XO6Ba8Ti6] embedded in a punctual charge set depicting the crystalline environment. The transition ions X are Fen+(n = 2, 3, 4, 5), Ti3+, Nb4+, and Nb5+. Some related defects like Fe(SINGLE BOND)Vo, where Vo stands for a lacunar oxygen site, are also investigated through a similar process. The positions of impurity levels insides the O2p(SINGLE BOND)Ti3d band gap are obtained from eigenvalues and related optical transition or ionization energies are calculated using excited states. This allows…

Simulation of tungsten tip-Al(100) surface electronic structure through LCAO-LSD calculations

1997

LDA electronic structure calculations on Au13 cluster

1997

Optical properties of Cr3+ and Ni2+ ions in MgO, LiNbO3 and LMA

1995

Abstract The electronic structures of Co2+ and Ni2+ ions are obtained by the molecular orbital LCGTO-LSD method. Electrostatic matrix calculations are performed for d3 and d8 configurations. Theoretical optical data are discussed in function of the impurity site location in the crystal cell.