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README.md

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+# Datasets curated from LeMaterial/LeMatBulkUnique/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.
+
+## 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.