---
language:
- en
tags:
- chemistry
- crystal
- material
size_categories:
- 1M<n<10M
---
# Datasets curated from LeMaterial/LeMatBulkUnique - unique_pbe version 1.0

This repository is aimed to contain a curated version of the PBE calculated part of LeMaterial dataset created by Entalpic
and available at "https://huggingface.co/datasets/LeMaterial/LeMat-BulkUnique" as "unique_pbe".

The curation was done using Pymatgen version 2024.10.3.

The curated dataset is given directly in CIF format for easy readability by usual crystal data reader softwares and python packages.
The CIFs were generated by pymatgen's CifWriter class, but the header containing the unique "material_id" key and the _entalpic_fingerprint line
containing the hash value generated by Entalpic's hash algorithm were added by us using a script modifying the already CifWriter-generated data.

## Curation steps

Were filtered out:
- All structures containing at least one rare gas element (group 18 of periodic table, i.e. He (Z = 2), Ne (Z = 10), Ar (Z = 18), Kr (Z = 36), Xe (Z = 54), Rn (Z = 86) and Og (Z = 118)).

- All structures containing at least one of the 28 elements with f-type orbital valence (from La (Z = 57) to Yb (Z = 69), and from Ac (Z = 89) to No (Z = 102)).

NOTE: Lu (Z = 90) and Lr (Z = 103) were not touched because their valence electron is actually in a d-type orbital, they are d1 elements just like Sc (Z = 21) and Y (Z = 39).

- All unphysical structures having at least a pair of atoms closer than 0.5 angströms.

- All structures considered equivalent by the StructureMatcher with default parameters of fractional length tolerance ltol = 0.2, site tolerance stol = 0.3, and angle tolerance angle_tol = 5.0 degrees.

NOTE: Even if we exctracted the initial data from the "Unique" dataset which passed Entalpic's hash algorithm, a lot of duplicates remained for the StructureMatcher.
We put an emphasis on this to underline the statement from Entalpic's own page that their hash method is not perfect yet, but it is still a very useful approach by its efficiency in order to do a pre-filtering task.

## Dataset files specifications

- The file simply named "lematerial.cif" contains all 2,838,937 structures that passed all curation steps mentionned above.
- The files whose name contain a crystal system name are crystal system specific subsets of the full dataset.
  The classification relies on the SpacegroupAnalyzer class of Pymatgen with default fractional coordinate tolerance of 0.01 and angle tolerance of 5.0 degrees.
- The data in the subsets is not symmetrized in order to have all true atomic positions as given in the original dataset and not ones estimated by symmetry operations.

### Subsets specifications
- "lematerial_triclinics.cif" contains 101,024 triclinic structures
- "lematerial_monoclinics.cif" contains 441,916 monoclinic structures
- "lematerial_orthorhombics.cif" contains 449,882 orthorhombic structures
- "lematerial_tetragonals.cif" contains 905,267 tetragonal structures
- "lematerial_trigonals.cif" contains 272,255 trigonal structures
- "lematerial_hexagonals.cif" contains 97,285 hexagonal structures
- "lematerial_cubics.cif" contains 571,308 cubic structures