# CFOUR_GAMMA_ABCD

> Used to control the handling and storage of two-particle density matrix elements with four virtual indices . DISK (=0) directs the program to calculate and store all elements of , while DIRECT (=1) tells the program to use alternative algorithms in which is calculated and used “on the fly”. Note that this option might be not available for all type of calculations.

> - Type: string
> - Possible Values: DISK, DIRECT
> - Default: DISK