$TRANS

$TRANS group

(optional for -CI- or -MCSCF-)
(relevant to analytic hessians)
(relevant to energy localization)

This group controls the integral tranformation. MP2 integral transformations are controlled instead by the $MP2 input group. There is little reason to give any but the first variable.

DIRTRF
= a flag to recompute AO integrals rather than storing them on disk. The default is .FALSE. for MCSCF and CI runs. If your job reads $SCF, and you select DIRSCF=.TRUE. in that group, a direct transformation will be done, no matter how DIRTRF is set.

Note that the transformation may do many passes over the AO integrals for large basis sets, and thus the direct recomputation of AO integrals can be very time consuming.

MPTRAN
= method to use for the integral transformation.

the default is try 0, then 1, then 2.
0 means use the incore method

1 means use the segmented method. This is the only method that works in parallel.

2 means use the alternate method, which uses less memory than 2, but requires an extra large disk file.

NWORD
= Number of words of fast memory to allow. Zero uses all available memory. (default=0)

CUTTRF
= Threshold cutoff for keeping transformed two electron integrals. (default= 10**(-9))

AOINTS
= defines AO integral storage during conventional integral transformations, during parallel runs. DUP stores duplicated AO lists on each node, and is the default for parallel computers with slow interprocessor communication, e.g. ethernet. DIST distributes the AO integral file across all nodes, and it is the default for parallel computers with high speed communications.


The remaining groups apply only to -CI- and -MCSCF- runs.


For hints on how to do -CI- and -MCSCF- see the 'further information' section


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