The Effect of Phonon Anharmonicity on the Thermodynamic Properties of Nonmetallic Solid

Germanium is used as an example for developing a self-consistent thermodynamic approach to the construction of a model of crystal lattice of a nonmetallic nonmagnetic solid. This approach takes into account the effect of anharmonicity of thermally excited phonons. The calculations of temperature dependences of basic thermodynamic functions reveal, for a model substance, very adequate agreement with the available experimental data in a wide temperature range of hundreds of kelvins.