metal_sdf/CA_ideal.sdf

CA
  -OEChem-03222417093D

  1  0  0     0  0  0  0  0  0999 V2000
    0.0000    0.0000    0.0000 Ca  0  2  0  0  0  0  0  0  0  0  0  0
M  CHG  1   1   2
M  END
> <OPENEYE_ISO_SMILES>
[Ca+2]

> <OPENEYE_INCHI>
InChI=1S/Ca/q+2

> <OPENEYE_INCHIKEY>
BHPQYMZQTOCNFJ-UHFFFAOYSA-N

> <FORMULA>
Ca+2

$$$$