Abstract :
A novel method is proposed to calculate the Debye frequency, speed of sound, and some other properties of ionic crystals and metal alloys from the plasma frequency of the ions. As an example of application, the theoretically obtained Debye temperatures T D of NaCl, KCl, RbI, AgBr, Cu3Au are 308 K, 238 K, 98 K, 149 K, and 296 K respectively, while an experiment gives 321 K, 235 K, 103 K, 140 K, and 285 K respectively. The reliability of calculated values of T D of the univalent and bivalent pure metals is characterized by R2≃0.985R2≃0.985. The hypothetical properties of solid under extremal conditions were estimated. For example, the metallic hydrogen has the theoretical determined View the MathML sourceTD≃4000K and the speed of sound 20 km c−1 at a pressure of 2.60 Mbar
Keywords :
A. Alloys , D. acoustical properties , D. Charge-density waves , D. lattice dynamics , A. Metals