A Transformer learned electron density well enough to skip the self-consistent loop: median total-energy error 0.036 meV
AspireAI community · arXiv (SwinUNETR-V2 / NeXtUNETR)
Transformer-inspired architectures for electron density, the central variable of density functional theory, reach state-of-the-art accuracy on QM9 with normalised mean absolute errors averaging 0.075% for SwinUNETR-V2 and 0.046% for the attention-free NeXtUNETR. The authors report the predicted densities are accurate enough that a single Kohn-Sham step reproduces the self-consistent electronic structure, with median errors of 0.036 meV in total energy, 0.65 meV/angstrom in forces and 1.8 meV in the HOMO-LUMO gap, and that the forces drive ab initio molecular dynamics. The models also transfer when fine-tuned on small datasets to systems with elements absent from QM9, but the headline result is measured on QM9-sized molecules.
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