From owner-chemistry@ccl.net Sat Nov 19 19:45:01 2011
From: "Eli Lam elizabeth.shlam(~)gmail.com" <owner-chemistry.:.server.ccl.net>
To: CCL
Subject: CCL: Tddft and tdhf accuracy
Message-Id: <-45902-111119194051-8594-aK4FZLVdz8QrFu5qltcq7A.:.server.ccl.net>
X-Original-From: "Eli  Lam" <elizabeth.shlam|-|gmail.com>
Date: Sat, 19 Nov 2011 19:40:47 -0500


Sent to CCL by: "Eli  Lam" [elizabeth.shlam-*-gmail.com]
Dear all,

I've learnt that tddft and tdhf both are methods for calculating excited states and electronic 
transitions.  I would like to ask which method is more accurate and give a "better" picture to an 
organometallic molecule's excited state, for example?  

I have learnt that tddft is not good for high excited states calculations but generally good for 
radicals.  But would it be good for neutral molecules too?  And in particular, I found tddft seems 
to have underestimated much for very conjugated systems. A friend said it's because tddft is 
based on ground state, and for excited states, hf does a better job.  I would like to ask for more 
views on that.  And would you please suggest some readings concerning the issue?  Thanks so 
much!

Regards, 
Eli