On influence from pseudopotential on phonon spectrum of diamond:First-Principles Study

Diamond is a kind of important superhard materials and has many attractive properties such as high hardness,wear-resistance,low friction coefficient and thermal conductivity,which directly related to phonon spectra.First-principles calculations which are based on density functional theory(DFT) have been carried out to study the influence of the different pseudopotential on the phonon spectrum of diamond.It has been found that the lattice constant and phonon spectral are different with different pseudopotentia,and the phonon frequency is larger,the difference of phonon spectral is more notable.This shows that the appropriate pseudopotentia is very important for the phonon spectral calculation.