TDDFT question

From: "Deng, Jun" <jdeng ( ( at ) ) ppg.com>
Subject: TDDFT question
Date: Wed, 7 Aug 2002 13:53:11 -0400

Hi,
 Does anyone has experience in TDDFT calculation on a charged molecule?
 I found that for neutral compounds, TDDFT generally gives smaller excitation
 energy than experiment for neutral compounds.  However, for charged molecules,
 it gives much, much higher energy.  Why?  Any suggestion?
 Thank you all in advance!
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 Jun Deng                                          440 College Park Drive
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 PPG Industries, Inc.                        E-mail: jdeng ( ( at ) ) ppg.com
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