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Vladimir A. Mironov
vladimir.a.mironov@gmail.com

On Sat Mar 26 '11 4:56pm, Gena wrote
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>On Sat Mar 26 '11 4:37pm, sanya wrote
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>>Probably, you have included CASSCF natural orbitals instead of optimized. Both sets of orbitals are punched; OPTIMIZED are in the last $VEC group.

>>An alternative is to set INORB=2 to ignore orthogonality check. But I'm not sure about the results with nonorthogonal orbitals.

>>On Fri Mar 25 '11 7:31pm, Gena wrote
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>>>On Fri Mar 25 '11 5:58pm, Gena wrote
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>>>>Hello!
>>>>I try to calculate electronic absorption spectra using XMCQDPT. But after CASSCF calculation is successfully finished, XMCQDPT calculation with optimized MOs from CASSCF PUNCH-file fails in the very beginning listing unorthogonal to each other orbitals, and as i see it - they're all unorthogonal. Firefly also advises me to set INORB=0 to reorthogonalize them. But as XMCQDPT isn't parallel, it isn't convenient. Moreover, i don't understand the difference, i thought that would be the same CASSCF calculation, only in serial mode. Sorry for stupid question, i'm just studying multiconfigurational methods. What am i doing wrong?
>Thank you, Sanya! No, of course i understand the difference between optimized and natural orbitals. Moreover, i tried to use natural orbitals to see what error would it cause. And i got immediately I/O error.
>The interesting for me thing is that i tried another compound with the same algorithm of actions, and the xmcqdpt calculation started successfully, passing orthogonality check without problems! (Though it isn't over yet).
>I too dislike to ignore unorthogonality as i really wanna get reliable results, because i need them in my experimental work.

[ This message was edited on Sat Mar 26 '11 at 9:06pm by the author ]