PSI - Issue 65

I.V. Kosarev et al. / Procedia Structural Integrity 65 (2024) 127–132 I.V. Kosarev, E.A. Korznikova, S.V. Dmitriev / Structural Integrity Procedia 00 (2024) 000–000

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respectively. The small amplitude modes of group G3 represent phonons at point H of the first Brillouin zone, where T1, T2, and longitudinal phonons have the same frequency.

Fig. 1. Initial displacements of the atoms used to excite the 14 one-component DNVMs in the bcc lattice. The displacements are shown as vectors in the plane, and the component of the displacement is shown as a dot, cross, or empty circle if it is positive, negative, or zero, respectively. The length of the initial displacement vectors is the same for all displaced atoms, although there are atoms with zero initial displacement that remain at rest while other atoms vibrate.

3. Results

The equilibrium lattice parameter for all three classical potentials is 3.03 Å, which is also in agreement with the experimental value, Arblaster (2018); the equilibrium parameter of the machine learning potential B2020 is 3.00 Å. The obtained frequency responses of the DNVMs for each of the potentials are presented in Fig. 2.