fig4

Figure 4. MLFF-predicted and DFT-computed relative energies, ΔE(λ), along the common Oct–Sqr structural interpolation path (λ), where λ = 0 and 1 correspond to Oct and Sqr, respectively. For each model, energies are referenced to its prediction for Oct at λ = 0, such that ΔE(λ) = E(λ) - E(0). Red circles denote predictions from the model fine-tuned on non-spin-polarized PBE data without U, while green diamonds and blue squares denote the model fine-tuned directly from its pretrained initialization to PBE+U and the model first fine-tuned on PBE without U and subsequently fine-tuned on PBE+U, respectively. All predictions are obtained with DPA4-Neo. Black triangles and stars represent static DFT-calculated energies from PBE+U and non-spin-polarized PBE, respectively. MLFF: Machine-learned force field; DFT: density-functional theory; PBE: Perdew–Burke–Ernzerhof.