Variation of the 13C Diamond Properties under Isothermal Compression

Abstract

The parameters of atomic interaction pair potential for ¹³C diamond have been determined from experimental data on the ratio of Raman frequencies for isotopically different diamonds. Based on these parameters, an equation of state and baric dependences of ¹³C diamond lattice properties at 300 K have been calculated. Specifically, the Debye temperature; the first, second, and third Grüneisen parameters; elastic modulus; thermal expansion coefficient; heat capacity; surface energy; and pressure derivatives of these parameters along a 300 K isotherm have been determined. The results have been compared with available data for diamond having a natural isotopic composition, i.e., for ^12.01C.