| 1:32:20 PM PST - Wed, Feb 10th 2016 |
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Hi all,
I'm currently running CDFT for a two fragments system which has an unpaired electron
fragment 1 is neutral, no unpaired electrons
fragment 2 is open shell, one unpaired electron, charge +1, mult 2
the whole dimer (unrestricted, unconstrained) experencies problems in convergence with DIIS so I (succesfully) used CGmin.
I also succeded in having converged "MOs" for each fragment, both evaluated with the unrescricted formalism (even fragment one, which per se would be closed shell)
Nevertheless when I try to compute the final step, i.e. the 'constrained dimer' I get the same result as unconstrained DFT. Indeed the "multiplier" string is not even written in NwChem output file.
Therefore it seems that the CGmin key disables CDFT
- Could anyone confrm what I'm supposing?
- Am I faced with a bug?
- Am I missing something relevant?
Any help would be appreciated.
Post Scriptum
I have also tested a very simple case: two ethylene molecules /6-31G* basis set , untwisted at 3 Angstrom, parallel planes. By using DIIS in CDFT, I get the localized state (e.g. charge on 1st ethylene) lying ca 1 eV above the fully delocalized state; using CGmin, CDFT solution collapses into standard DFT one.
(NWCHEM6.6 full patched LINUX 64 default libraries, MPI)
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