The lattice dynamics of tin telluride

The frequencies of normal modes of vibration propagating in high symmetry directions in tin telluride at 100 °K have been measured by means of inelastic neutron scattering techniques. The shape of the longitudinal optic branches is dominated by the screening effects of the free carriers in the crystal. We have developed a modification of the shell model in which this screening is included in a consistent way, and we are able to obtain a satisfactory description of the dispersion curves using this model with an ionic charge of 134e, and a slightly worse fit using a non-ionic model. Both these models were based on the Hartree dielectric function, and were found to be superior to a model based on the Thomas-Fermi dielectric function.

[1]  M. Elcombe The crystal dynamics of lead sulphide , 1967, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[2]  W. Cochran,et al.  The crystal dynamics of lead telluride , 1966, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[3]  R. Cowley,et al.  Conduction Electrons and Optic Modes of Ionic Crystals , 1965 .

[4]  R. Cowley On the theory of ferroelectricity and anharmonic effects in crystals , 1965 .

[5]  J. Babiskin,et al.  Shubnikov-de Haas Effect in SnTe , 1965 .

[6]  G. Gilat,et al.  A NEW SAMPLING METHOD FOR CALCULATING THE FREQUENCY DISTRIBUTION FUNCTION OF SOLIDS , 1964 .

[7]  G. Pratt,et al.  Relativistic Effects in the Band Structure of Pbte , 1963 .

[8]  R. Giacconi,et al.  Further Evidence for the Existence of Galactic x Rays , 1963 .

[9]  W. Cochran Lattice dynamics of sodium , 1963, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[10]  W. Cochran,et al.  LATTICE DYNAMICS OF ALKALI HALIDE CRYSTALS. III. THEORETICAL , 1963 .

[11]  R. Cowley The elastic and dielectric properties of crystals with polarizable atoms , 1962, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[12]  W. Cochran,et al.  Lattice Dynamics of Alkali Halide Crystals , 1960 .

[13]  E. Kellermann Theory of the vibrations of the sodium chloride lattice , 1940, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[14]  A. Maradudin Theoretical and Experimental Aspects of the Effects of Point Defects and Disorder on the Vibrations of Crystals—1 , 1966 .

[15]  R. F. Brebrick Deviations from stoichiometry and electrical properties in SnTe , 1963 .

[16]  M. Born,et al.  Dynamical Theory of Crystal Lattices , 1954 .