Studying Phonons in Diamond using MD

We studied the evolution of the Vibrational Density of States (VDOS) of diamond nanoparticles (NP) under indentation by means of molecular dynamics simulation with LAMMPS. In the work, we study NPs of 5, 10, and 20 nm in diameter at 300 K and we generate the VDOS from the velocity autocorrelation function (VACF) calculated in LAMMPS. We observe that the high-frequency peak is reduced as a function of the strain applied to the NPs until a 35 % of decrease. In the presentation, we will show the dependence of the intensity of the peaks with the strain and we will compare it with the case of diamond bulk with vacancies. These results claim a comparison between both situations, one easier to simulate than the other.