manual   quickstart   instguide   update   basis

Next: 51.4 Harmonic vibrational frequencies Up: 51 BASIS SET EXTRAPOLATION Previous: 51.2 Extrapolation functionals   Contents   Index   PDF

51.3 Geometry optimization using extrapolated energies

Geometry optimizations are possible by using numerical gradients obtained from extrapolated energies. Analytical energy gradients cannot be used.

The following possibilities exist:

1.) If OPTG directly follows the EXTRAPOLATE command, the extrapolated energy is optimized automatically (only variable settings may occur between EXTRAPOLATE and OPTG).


Extrapolating the energy for the last command:

Extrapolating the energy computed in a procedure:

Note that this is not possible if EXTRAPOLATE gets the input energies from variables.

2.) Using a procedure for the extrapolation:

By default, variable ECBS is optimized, but other variables (e.g. ECBSD) can be specified using the VARIABLE option on the OPTG command. 2018-03-24