title: Pseudo Jahn-Teller origin of perovskite multiferroics, magnetic-ferroelectric crossover, and magnetoelectric effects: the d0-d10 problem.
abstract: The conditions of multiferroicity in d(n) perovskites are derived from the pseudo Jahn-Teller effect, due to which ferroelectric displacements are triggered by vibronic coupling between ground and excited electronic states of opposite parity but same spin multiplicity; it takes place for some specific d(n) configurations and spin states only. In combination with the high-spin-low-spin crossover effect this leads to a novel phenomenon, the magnetic-ferroelectric (multiferroics) crossover which predicts magnetoelectric effects with exciting functionalities including electric magnetization and demagnetization.
authors.affiliation: Institute for Theoretical Chemistry, The University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Isaac B
authors.initials: IB
authors.lastname: Bersuker