ELASTIC CONSTANTS OF MERCURY SELENIDE

The elastic constants of mercury selenide from 4.2 to 300 K have been determined from 10-MHz sound-velocity measurements utilizing the pulse-echo technique. The constants c11, c12, and c44 range from 6.900×1011, 5.105×1011, and 2.3073×1011 dyn/cm2, respectively, at 0 K to 5.950×1011, 4.307×1011, and 2.2015×1011 dyn/cm2, respectively, at 300 K. The shear modulus cs=0.899×1011 dyn/cm2, compressibility el=1.753×10-12 cm2/dyn, and the low-temperature limit of the Debye characteristic temperature 0el=151 K are deduced from values of the elastic constants at 0 K obtained by extrapolation. The reststrahlen frequency as given by the Szigeti relation is 5.12×1013 Hz. From theoretical and empirical relations, the ionicity of HgSe is estimated to be e*e=0.70.1. The behavior of the elastic constants and the ionicity of HgSe are compared with the characteristics of other II-VI compounds that have the zinc-blende crystal structure. © 1969 The American Physical Society.