rohf ccsd(t) memory problems nwchem 6.3


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Gets Around

You have a few issues here:

TCE
 SCF
 FREEZE CORE ATOMIC
 CCSD(T) 
 PRINT t1
 tilesize 35
 attilesize 40
END


First, the local memory requirement (stack, not global) is tilesize^6 for (T) so you should use a tilesize of 20 or 24 to start.

Second, TCE is memory optimized for RHF and ROHF references using the 2eorb option, which will have a dramatic effect on the memory requirements, especially of the four-index transformation.

It doesn't affect the memory usage, but attilesize is only used for 2emet options greater than 1, which are themselves only in effect when 2eorb is used.

By the way, freeze core atomic is just freeze atomic. You need to provide a non-zero number to the core argument for it to do anything. The manual has details.