Note

This website is presently under development. The primary website for MOPAC is still http://openmopac.net until the majority of its contents have been migrated here.

SINGLET

Targets a singlet spin state in all calculations, which is a synonym for MS=0. See the MS keyword for more information.

Singlet states are already the default for Hartree-Fock calculations, but this keyword can force the target of configuration interaction calculations to be a singlet state rather than the lowest-energy integer-spin state.