The number of structures and the run times are listed for MOLGEN 5.0, MAYGEN and OMG (molecules do not contain N, P or S). A more diverse set of molecular formulae is benchmarked in Table . Molgen 5.0 has an aromaticity filter that filters out resonance structures of substituted aromatic molecules. This filter is activated by default and therefore Molgen 5.0 generates fewer structures than Molgen 3.5 and MAYGEN. Figure : Timing of structure generation runs with MOLGEN 5.0, MAYGEN and OMG for molecular formulae containing carbon, hydrogen, oxygen and halogens, but not containing nitrogen, phosphorus or sulfur. The latter were omitted to keep fair conditions because OMG generates additional structures with higher oxidation states for those omitted elements.