Lattice Dynamics of ZnTe and CdTe

Abstract

The model used is a rigid-ion model with an effective ionic charge including general interactions for nearest and next nearest neighbours and long range Coulomb interactions. It provides a good fit with recent neutron data for ZnTe and CdTe on condition that no hypothesis is made a priori on the interatomic forces and that the eleven parameters given by the model are used. E s wird ein Modell starrer Ionen mit einer effektiven Ionenladung benutzt, unter Einbeziehung allgemeiner Wechselwirkungen fur nachste und iibernachste Nachbarn und langreichweitiger Coulomb-Wechselwirkungen. Es liefert eine gute Anpassung an neuere Neutronendaten fur ZnTe und CdTe unter der Voraussetzung, dal3 a priori keine Hypothese iiber die interatomaren Krafte gemacht wird, und dal3 die elf Parameter, die das Modell liefert, benutzt werden.A rigid-ion model (RIM) with four parameters was used to calculate the phonon dispersion curves for ZnTe [5] and to study localized substitutional impurity modes in compounds having zincblende structure including CdTe and ZnTe [B]. A seven-parameter RIM was used later to calculate the CdTe and ZnTe phonon dispersion curves [7]. I n both cases the determination of the force constants was based only on optical data and on experimental values of the elastic constants Cll, C12, Cd4, and a noticeable lack of agreement was found between the phonon dispersion curves thus calculated and the neutron scattering data obtained afterwards [8,9].Kunc [lo, 111 gave a dynamic description of 15 compounds having the zincblende crystal structure; these include ZnS, ZnSe, CdTe, ZnTe but for the last two, in the absence of neutron scattering data, the description was incomplete. l) B.P. 2, 91 190 Gif-sur-Yvette. } 352 52 113-6. Discussion A first observation is the high sensitivity of the C branches to the values of the parameters El and E,. This is illustrated by the CdTe phonon dispersion curves calculated for El = E, = 0, using the values of Table 1 for the other parameters. The conclusion is that a priori hypotheses on short-range forces reducing the number of parameters (for instance the assumption of central

On the Optical, Thermal, and Vibrational Properties of Nano-ZnO:Mn, A Diluted Magnetic Semiconductor

“…To start with, the Green functions for the ZnO host system are evaluated from the phonons and eigenvectors, which are computed from the refined rigid ion model developed by Plumelle and Vandevyver [36].…”

Debye–Waller factors of zinc-blende-structure materials – a lattice dynamical comparison

“…Correction to model A: 2 = -0.471 (S. K. Sinha, private communication); (e) Vandevyver & Plumelle (1978); (f) Dolling & Waugh (1965); (g) Borcherds & Kunc (1978); (h) ; (i) Price, Rowe & Nicklow (1971); (j) Jaswal (1978c); (k) Talwar, Vandevyver & Zigone (1980); (l) Vagelatos, Wehe & King (1974); (m) Jaswal (1978a); (n) Plumelle and Vandevyver (1976); (o) Rowe,Nicklow,Price & Zanio (I 974); (p) Kepa, Giebultowicz, Burras, Lebech & Clausen (1982), parameters in private communication from H. Kepa; (q) Kepa et al (1982), parameters from Kepa (1980); (r) Prevot, Hennion & Dorner (1977), published parameters are inadequate; those to full accuracy obtained from B. Prevot (private communication); (s) Jaswal (1978b); (t) Plumelle, Talwar, Vandevyver, Kunc & Zigone (1979) Table 1 summarizes all the materials and the source lattice dynamical models considered here. These models are the best ones available, all having been fitted to phonon frequencies measured by neutron scattering.…”

Lattice dynamical investigations on Zn diffusion in zinc oxide

“…The displacements of the atoms due to the presence of impurity is considered as a perturbation in the form of matrix called scattering matrix (Plumelle and Vandevyuer 1976). When a plane wave u 0 passes through the defect space consisting of the defect and the neighbours in the diffusion ring, the defect problem has to be treated as scattering mechanism with u as the displacement matrix giving the displacement of the scattered wave w, as u = u (0) + w, where the matrix u 0 corresponds to the displacement matrix of a perfect lattice to be obtained from the solution of the time independent equation (9) and the solution is Lu 0 = 0, where the matrix L is defined in terms of the force constants, , as…”