Fig. 4: Phonon spectrum of diamond.

Phonon dispersion relation for diamond as predicted by HotPP1 (blue dotted) and HotPP2 (red dotted) with comparison to DFT reference data (black solid). The HotPP1 was trained with the dataset GAP2017³⁷, and the HotPP2 was trained with GAP2020³⁸. Source data are provided as a Source Data file.