Input Data Blocks Needed by RELAX

$intdef or $redundant

Definitions of internal coordinates and, optionally, values of internal coordinates (val=..., given in a.u. or degrees) or force constant diagonal elements (fdiag=...).

$grad

Cartesian coordinates and gradients calculated in subsequent optimization cycles. Entries are accumulated by one of the gradient programs (grad, mpgrad, rimp2, ricc2, egrad, etc.).

$egrad

Basis set exponents scale factors and their gradients as calculated in subsequent optimization cycles. Entries are accumulated by one of the gradient programs.

$globgrad

Global scale factors and gradients as calculated in subsequent optimization cycles. Entries are accumulated by the grad or aoforce program.

$corrgrad

Allows to augment internal SCF gradients by approximate increments obtained from treatments (e.g. correlation or relativistic) on higher level. See the example below.

$corrgrad
#  coordinate    increment
     1            0.0600
     8           -0.0850

$forceapprox options

Approximate force constant matrix (as needed for geometry optimization tasks). The storage format may be specified by the
available options:

format=format

the default format is format=(8f10.5), but other 10-digit f10.x formats (e.g. x=4,6,..) are possible and will be used, after being manually specified within $forceapprox. See the example below:

$forceapprox  format=(8f10.4)
    0.9124
    -.0108    0.3347
    0.2101    0.0299    1.3347
    0.0076    0.1088    0.0778    0.6515

$hessian (projected)

this data block contains the analytical cartesian force constant matrix (with translational and rotational combinations projected out) as output by the aoforce program and may be used to supply a high quality force constant matrix $forceapprox for geometry optimizations (specifying $forceinit on carthess, or $interconversion cartesian -> internal hessian).