Effect of chemical nature of atoms on the electronic, dielectric, and dynamical properties of ABX3 halide perovskite. Issue 10 (3rd February 2020)

• Record Type: Journal Article
• Authors: Ben Sadok, Raouia; Plugaru, Neculai; Birsan, Anca; Kuncser, Victor; Hammoutène, Dalila
• Is Part Of: International journal of quantum chemistry. Volume 120:Issue 10(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-02-03
• Subjects: density functional theory -- dielectric properties -- dynamical properties -- electronic properties -- halide perovskite; Quantum chemistry -- Periodicals; 541.28
• DOI: 10.1002/qua.26172
• Languages: English
• ISSNs: 0020-7608

Abstract

Abstract: First‐principles calculations within density functional theory were performed on a series of halide perovskite compounds ABX 3 ( A : Cs or Rb ; B : Pb or Sn ). Their electronic structure, lattice dynamics, and dielectric properties were studied in relationship with the change in atom species at each one of the three inequivalent crystallographic sites, to explain the origin of these properties. Thus, the variation of the bandgap with the overlap between the B cation lone pair and the electronic states of halide atoms, as well as with the distortion of the BX 6 octahedra network is discussed. It is shown that the vibrational modes, phonon frequencies, atomic displacements, and the possible ferroelectric instability in these compounds are dependent on masses of atoms, volume of AX 12 polyhedron, as well as on streoactivity of Pb lone pair. Also, the Born effective charges, dielectric constant, spontaneous polarization, and infrared spectra are calculated. The relation between these dielectric properties and the ions dynamics is discussed. Abstract : First principles calculations were performed to explain which factors control the bandgap, the dynamics of atoms and spontaneous polarization in several ABX 3 halide perovskites. Results evidencing the origin of these properties and their variation with cation species and crystal structure are reported. The variation of orbitals overlap, the stereoactivity of B cation lone pair, the X ‐ B ‐ X arrangement, and electrostatic interactions are shown to mainly determine the specific properties of each compound.