title: Structural, electronic, and ferroelectric properties of compressed CdPbO3 polymorphs.
abstract: By means of first-principles calculations based on density functional theory (DFT) and hybrid functional, we  studied the structural, electronic, and ferroelectric properties of the two recently synthesized high-pressure perovskite-type (orthorhombic, space group Pnma) and LiNbO(3)-type (rhombohedral, space group R3c) polymorphs of CdPbO(3). Besides providing structural and electronic results in good agreement with available experiments, our results are able to correctly describe the pressure-induced Pnma → R3c structural phase transition and most importantly predict the realization of proper ferroelectric behavior in LiNbO(3)-type CdPbO(3) with an electric polarization of 52.3 μC/cm(2). The proper covalent interaction mechanism driving the ferroelectric transition is discussed and explained in terms of the analysis of Born effective charges, potential-energy surfaces, charge density isosurfaces, and electric localization function.
authors.affiliation: Key Laboratory of Applied Chemistry, Yanshan University, Qinhuangdao 066004, China.
authors.forename: Yuanhui
authors.initials: Y
authors.lastname: Xu
authors.forename: Xianfeng
authors.initials: X
authors.lastname: Hao
authors.forename: Cesare
authors.initials: C
authors.lastname: Franchini
authors.forename: Faming
authors.initials: F
authors.lastname: Gao