Gaussian 03 Online Manual
Last update: 2 October 2006


The method keywords request a semi-empirical calculation using the PM3 Hamiltonian [55,56]. The parameter for Li has been updated as specified in [402]. PM3MM specifies the PM3 model including the optional molecular mechanics correction for HCON linkages. No basis set keyword should be specified with either of these keywords.

Energies, "analytic" gradients, and numerical frequencies.

The PM3 energy appears in the output file as follows (followed by the x, y, and z components of the dipole moment):

Energy=    -.080731473251 NIter=  10. 
Dipole moment=   .000000   .000000  -.739540

The energy is as defined by the PM3 semi-empirical model. Note that energy differences computed from the values in semi-empirical calculations are in Hartrees and may be compared directly with energy differences computed from jobs using other methods.