xnn.common.data.hub.ani1

ANI-1 dataset builder (pyanitools HDF5 from figshare).

The ANI-1 data set holds ~20 million off-equilibrium conformations and DFT (wB97X/6-31G(d)) total energies for 57,462 small organic molecules (H, C, N, O) built from GDB-11, generated by Normal Mode Sampling. It is distributed as eight HDF5 files ani_gdb_s0X.h5 (X = number of heavy atoms, 1-8) bundled in a single ~4.8 GB ANI-1_release.tar.gz archive.

Reference

Smith, Isayev & Roitberg, “ANI-1, A data set of 20 million calculated off-equilibrium conformations for organic molecules”, Sci. Data 4, 170193 (2017). Data: https://doi.org/10.6084/m9.figshare.c.3846712 Format / reader spec: isayev/ANI1_dataset

Notes

• Upstream energies are in Hartree and positions in angstrom. By default energies are converted to eV (the convention used elsewhere in xnn); units="hartree" keeps the raw values. The molecule contains no forces.

• The whole 4.8 GB archive is downloaded once (cached and MD5-verified), even to read a single heavy-atom subset. Use heavy_atoms to select subsets and max_molecules / max_conformations to cap the amount materialised – the full set is ~20 M conformations and will not fit in memory at once.

• ANI-1 ships no official split. split in {"train", "val", "test"} applies the paper’s per-molecule 80/10/10 partition with a fixed seed, so splits are disjoint and reproducible; split=None returns {"all": ...}.

Classes

ANI1Builder()

Builder for the ANI-1 data set (20M DFT energies, GDB-11 subsets).