Phonopy

Phonopy is an open-source Python-based software package used for calculating phonon properties in crystalline materials. It is widely utilized in materials science and solid-state physics to determine phonon dispersion relations, density of states, thermal conductivity, and thermal properties like heat capacity and entropy. Phonopy uses force constants from density functional theory (DFT) calculations to model lattice dynamics and vibrational behavior of materials, providing insights into stability, thermal expansion, and electron-phonon interactions, which are critical for understanding and designing advanced materials.

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