First-principles investigation of SrBi 2 Ta 2 O 9

STACHIOTTI, M. G.; RODRIGUEZ, C. O.

FERROELECTRICS

TAYLOR & FRANCIS LTD

Año: 2000 vol. 237 p. 49 - 56

0015-0193

The electronic structure of SrBi2Ta209 (SBT) is investigated from first-principles, within thelocal density approximation, using the full-potential linearized augmented plane wave(LAPW) method. The results show that, besides the large Ta(5d)-0(2p) hybridization whichis a common feature of the ferroelectric perovskites, there is an important hybridizationbetween bismuth and oxygen states. The role played by these two covalent bonds for drivingthe ferroelectric instability in SBT is investigated