Memory UHF-based TCE

Clicked A Few Times	3:35:40 PM PDT - Mon, Aug 31st 2015 Dear NWchem experts, I am trying to do some UHF-based coupled cluster calculations using TCE (CCSD(T) and post-CCSD(T)). It always requires a huge amount of memory. I want ask two questions on reducing the memory demand. 1) Are all 2eorb and 2emet options unavailable for UHF-based CC calculations? 2) Can all parallel I/O options be applied to UHF-based CC calculations? I am using NWchem 6.5. Thanks a lot! YUGE

Clicked A Few Times	5:01:44 PM PDT - Mon, Aug 31st 2015 Hi Yuge, You cannot use 2eorb option in the context UHF TCE runs they were designed to deal with RHF and ROHF cases. The only option you have to run TCE UHF calculations is to use the standard spinorbital 4-index transformation. There is disk version of this algorithm - but it will be pretty slow. Please try to add "2emet 2" option to your tce input group. Best, Karol

Clicked A Few Times	8:52:12 PM PDT - Mon, Aug 31st 2015 Karol, Thank you for the reply!

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