• Checker searches for explicit hydrogens.
  
  The following different types of explicit hydrogens can be searched:

  • Lonely: hydrogen atom without connection (:lonely=true)

  • Isotopic: hydrogen isotopes (:isotopic=true)

  • Charged: charged hydrogen atoms (:charged=true)

  • Radical: hydrogen radicals (:radical=true)

  • Mapped: mapped hydrogens (:mapped=true)

  • Wedged: hydrogen connecting with wedged bond (:wedged=true)

  • H Connected: hydrogen connected to a hydrogen atom (:hconnected=true)

  • Polymer End Group: hydrogen connected to a SRU S-group (:polymerendgroup=true)

  • S-group End: hydrogen connected to a Superatom S-group (:sgroupend=true)

  • S-group: hydrogen which is the only atom in an S-group (:sgroup=true)

  • Valence Error: hydrogen connected to an atom which has valence error (:valenceerror=true)

  • Bridgehead: hydrogen connected to a bridgehead atom (:bridgehead=true)

This picture summarizes the applied categorizations:

• The corresponding fixer offers removing explicit hydrogens and the selected special atoms (removeexplicith).

Example :