KR
  -OEChem-04192423343D

  1  0  0     0  0  0  0  0  0999 V2000
    0.0000    0.0000    0.0000 Kr  0  0  0  0  0  0  0  0  0  0  0  0
M  END
> <OPENEYE_ISO_SMILES>
[Kr]

> <OPENEYE_INCHI>
InChI=1S/Kr

> <OPENEYE_INCHIKEY>
DNNSSWSSYDEUBZ-UHFFFAOYSA-N

> <FORMULA>
Kr

$$$$