public_sql_98/atom.csv

original_column_name,data_format,combined_description
atom_id,text,Unique identifier for the atom.
molecule_id,text,Identifier of the molecule to which the atom belongs. Atom IDs follow the pattern TRXXX_i for the ith atom of molecule TRXXX.
element,text,"Chemical element of the atom, using lowercase standard symbols (e.g., c, h, o, n, s, cl, p, na, br, f, i, sn, pb, te, ca)."