The calculation of radial and tangential force constants for nickel using an experimental phonon spectrum

Abstract

The possibility of calculating radial and tangential force constants, as well as elastic constants of face-centered cubic (FCC) metals, has been demonstrated for the case study of nickel on the basis of the experimentally measured phonon spectrum, which is theoretically described by the DeLaunay model in terms of the dynamic matrix D(q). The proposed calculation procedure is an alternative to the Born–von Karman model, which is widely applied for the description of the phonon spectrum in terms of force constants for interatomic interactions and in calculations of elastic constants using the phonon spectrum. The reliability of the obtained force constants for phonon spectrum was verified by comparison between the experimental and calculated data for the phonon spectrum and elastic constants for nickel. The obtained values of force constants for nickel have been compared with the theoretically calculated values using the pseudopotential method.