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.

STATIC

The static polarizability is calculated. An electric field gradient is applied to the system, and the response is calculated. The dipole and polarizability are calculated two different ways, from the change in ΔH_f and from the change in dipole. A measure of the imprecision of the calculation can be obtained by comparing the two quantities. Greater precision can be obtained by increasing the precision of the SCF (RELSCF=0.1 or RELSCF=0.01).

In 2004, the polarizability volume reported was modified by the use of additive corrections.

In STATIC, 37 or 38 SCF calculations are involved. The polarizability involves 36 calculations, one for each electric field. The fields are +X, -X, +2X, -2X, +Y, -Y, +2Y, -2Y, +X+Y, -X+Y, -X-Y, +X-Y, +2X+2Y, -2X+2Y, -2X-2Y, +2X-2Y, +Z, -Z, +2Z, -2Z, +X+Z, -X+Z, -X-Z, +X-Z, +2X+2Z, -2X+2Z, -2X-2Z, +2X-2Z, +Y+Z, -Y+Z, -Y-Z, +Y-Z, +2Y+2Z, -2Y+2Z, -2Y-2Z, and +2Y-2Z. These are used in the construction of a three by three secular matrix, which is then diagonalized, giving the orthogonal polarizabilities.

See also `POLAR <polar.html>`__