17th Group

  • Default:HF, HCl, HBr, HI, HAt

  • Molecules:

    • Neutral atoms: 1 bond is allowed.
      Exceptions:

      • 3 valence:

        • Two of the ligands should be F, Cl or oxygen; and one more atom from the 14th, 15th, 16th columns.

        • Double bonded oxygen and one any other atom from 14th, 15th, 16th columns are also accepted.

      • 5 valence:

        • Four of the ligands should be F, Cl or oxygen; and one more atom from the 14th, 15th, 16th columns. Double bonded oxygens are accepted.

      • 7 valence:

        • IF7 is accepted.

      • Halogen oxoacids:

        • HXOy, where X = Cl, Br, I or At; and y = 2, 3 or 4.

  • Ions:

    • F-, Cl-, Br-, I-, At- are accepted.

    • 1+ charged ions: 2 filled valences are necessary (bonds or radicals). If absent, implicit Hydrogen atoms added.

  • Radicals:

    • 1 Radical with 0 bond around the halogen atom is accepted.