Number of configurations: To ensure parameterequation balance for fitting accuracy, it is imperative to generate a sufficient number of training configurations for DFT force calculations. Lower-symmetry crystals generate more symmetry-independent IFC parameters and necessitate a more extensive sampling of atomic configurations to accurately describe IFC-governing phonon behaviors and vibrational properties, especially when handling anharmonicity. Our determination of configurations is based on two aspects: (i) Symmetry factor, which is set to 1 for the cubic system. Other crystal systems use the factor expressed as 48/N symm , where N symm is the number of point group symmetry operations and 48 is the highest symmetry operation number for O h point group, (ii) Site factor, which is set as the number of atoms in a primitive cell divided by 2. We multiply the two factors and round it to the nearest integer as the configuration number for each displacement. The default set of displacements are [0.01 Å, 0.03 Å, 0.08 Å, ). We note that usually, a handful (<10) of perturbed structures prove adequate for extracting higher-order force constants in simple cubic systems such as rocksalt and zincblende (Figure and Table ).