Author Topic: Two conponent ricc2 calculation  (Read 5550 times)

tayed

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Two conponent ricc2 calculation
« on: October 10, 2011, 09:03:44 AM »
Hi everybody,

 I'm trying two do two do two component ricc2, the job is ended normally, but i have a questiion
in the output ricc2.out i have this information:
Energy of reference wave function is     0.0000000000000 I can't unterstand why?

Normally this value must be equal to the wave function fund on ridft calculation?

Any explication

Thanks in advance

antti_karttunen

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Re: Two conponent ricc2 calculation
« Reply #1 on: October 10, 2011, 09:30:17 AM »
Hi,

Isn't the two-component formalism implemented only for HF and DFT calculations(at least according to manual)?

Best wishes,
Antti

uwe

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Re: Two conponent ricc2 calculation
« Reply #2 on: October 10, 2011, 11:43:37 AM »
Hello,

you are both right: ricc2 is able to do two-component MP2 energy calculations, but this is not printed in the documentation (unfortunately).

Tayed: The energy of the Hartree-Fock step in ricc2 is simply read from the $energy keyword and is not re-computed from the orbitals. So ricc2 itself only computes the correlation energy. If the HF energy is zero, then you did start ricc2 from a job which did not contain an entry in the $energy section. In most cases $energy is written to an own file called energy - I guess you did copy the input files without energy and started ricc2 in the new directory ?

Regards,

Uwe