------------------------------------------------------------------------ derivative data groups '$drvopt, $drvtol' ------------------------------------------------------------------------ option | status | description : ------------------------------------------------------------------------ crt | T | CARTESIAN 1st derivatives sec | T | CARTESIAN 2nd derivatives bas | F | energy derivatives with respect to | | BASIS SET exponents/scaling factors/ | | contraction coefficients glb | F | energy derivative with respect to | | a GLOBAL scaling factor dip | T | cartesian 1st derivatives of DIPOLE MOMENT pol | T | nuclear contribution to POLARIZABILITY fa | F | SPECTROSCOPIC ANALYSIS only tol 0.100D-06 derivative integral cutoff ------------------------------------------------------------------------ use <opt> for enabling, -<opt> for disabling of logical switches <&> will bring you back to GENERAL MENU without more changes <RETURN> OR * OR q(uit) WILL TERMINATE THIS MENUThe handling of these options is very simple. With the exception of

`tol`

, all are logical switches which are either true (or on,
active) or false (or off, inactive). You can switch between the two
states if you enter, for example, `crt`

(to switch calculation of
Cartesian first derivatives on) or `-crt`

(to switch it off). The
options `crt`

, `sec`

and `bas`

should provide no
problems. `glb`

refers to a global scaling factor for all basis
set exponents. Imagine that you would like to replace your basis set,
which contains basis functions
by another basis set which contains basis functions

where is the same for all primitive basis functions . With command

`glb`

you are able to calculate
analytical derivatives of the total energy with respect to
and can thus easily determine the optimum .
`dip`

enables you to calculate the first derivatives of the
electric dipole moment with respect to nuclear displacements which
gives you infrared intensities. `pol`

allows you to calculate the
contribution of the nuclear rearrangement on the electric
polarizability. `fa`

finally performs only a frequency analysis
which means that `aoforce` will read the force constant matrix
(`$hessian` or `$hessian (projected)`), diagonalize it and
give you the frequencies and normal modes. `tol`

is not a logical
switch as the other options in this menu, but a cutoff threshold for
the derivative integrals, i.e. integrals below this threshold will be
neglected in the derivative calculations.

Entering `*`

will bring you to the second derivative submenu.