From owner-chemistry /at\ccl.net Wed Nov  2 08:53:00 2011
From: "Ramon Crehuet rcsqtc^^iqac.csic.es" <owner-chemistry+/-server.ccl.net>
To: CCL
Subject: CCL:G: TDDFT question
Message-Id: <-45809-111102084258-29378-yu44WBfbxtIDGY7A/XA3wA+/-server.ccl.net>
X-Original-From: Ramon Crehuet <rcsqtc*o*iqac.csic.es>
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Date: Wed, 02 Nov 2011 13:46:26 +0100
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Sent to CCL by: Ramon Crehuet [rcsqtc() iqac.csic.es]
Dear all,
I do not know how to interpret some TDDFT results calculated with gaussian 09 
and CAM-B3LYP functional.
If I calculate triplet excited states from the ground state singlet, their 
energies are very close (in eV):
3.3, 3.4, 3.5, 3.5, 3.5, 3.6
If I calculate the lowest triplet state with CAM-B3LYP, it lies 4.2eV above the 
singlet. Is the error of 0.9eV normal? (this triplet corresponds to a pi-pi* 
excitation in a pyridine)
If, from this triplet, I calculate with TDDFT more triplet excited states, I get 
the energies:
0.7, 1.2, 2.0, 2.3, 2.5, 2.7
So all the close-lying triplets found before are gone.
My system contains 2 Au atoms coordinated to phosphines and pyridines (through a 
triple CC bond). I can tell you more structural details if you need them.
I am thankful to any advice,
Ramon