Properties of Cu1-xWx alloys at high pressure and high temperature from first-principles calculations

The electronic structures, elastic properties and thermodynamic properties of three different proportions of copper tungsten alloys (Cu3W, CuW, CuW3) at ground state, high temperature and high pressure are investigated by using the combined method of the first-principles calculation method based on density function theory. The calculated elastic constants indicate that Cu3W has an unstable structure and the CuW and CuW3 have the stable structures, which are in agreement with the phonon spectrum result. The metallic bond increases and the curve of the density of states moves toward the deep level with the increase of pressure. The quasi harmonic Debye model and the quasi harmonic approximation model are employed to calculate the bulk moduli, thermal expansion coefficients, Debye temperatures and specific heats of the Cu1-xWx alloys at different temperatures and different pressures.