This keyword controls the algorithm used for integral transformation, as well as the types of transformed integrals produced.
The default is the smallest set of integrals the method can use.
Direct
Requests that the direct transformation routines be used. Equivalent to L804. Link 804 will select between the in-core, fully direct, and semi-direct methods automatically. This is the default.
InCore
Forces use of the in-core algorithm in Link 804.
FullDirect
Forces use of the fully direct (MO integrals in core) method in Link 804.
SemiDirect
Forces use of the semi-direct algorithm in Link 804.
Full
Forces a transformation over all orbitals (i.e., including transformed integrals involving all virtuals). ABCD is a synonym for Full.
IJAB
Produce only <IJ||AB> integrals.
IAJB
Produce <IJ||AB> and <IA||JB> integrals.
IJKL
Produce <IJ||AB>, <IA||JB>, and <IJ||KL> integrals.
IJKA
Produce <IJ||AB>, <IA||JB>, <IJ||KL>, and <IJ||KA> integrals.
IABC
Produce <IJ||AB>, <IA||JB>, <IJ||KL>, <IJ||KA>, and <IA||BC> integrals.
Last update: 23 April 2013