Gaussian 03 Online Manual
Last update: 2 October 2006


This method keyword requests a semi-empirical calculation using the AM1 Hamiltonian [43,48,49,53,54,397,398,399,400,401,402]. No basis set keyword should be specified.

Energies, "analytic" gradients, and numerical frequencies.

The AM1 energy appears in the output file as follows (followed by the x, y, and z components of the dipole moment):

Energy=    -.091965532835 NIter=   10. 
Dipole moment=  .000000    .000000   -.739540

The energy is as defined by the AM1 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.