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Message-ID: <51004.169.237.93.196.1216249214.squirrel@vega.umcs.lublin.pl>
Date: Thu, 17 Jul 2008 01:00:14 +0200 (CEST)
Subject: [NWCHEM] which vertical excitations are the most important
From: piotrek@vega.umcs.lublin.pl
To: nwchem-users@emsl.pnl.gov
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Dear NWChem users,

  I am beginner in area of excited states calculations,
 so probably there are very silly questions (basically refers to TDDFT):

Is it correct, that if someone tries to identify the peaks on UV spectra,
he/she needs only focus on the vertical excitations with non-zero
oscillation strength (the stronger oscillation the greater relative peak
area?) ?

  How relevant are the other vertical excitations (those with oscillation
strength=0, in particular, the lowest excitations)?
 Are they important for photo-excitations (not necessary UV), even if they
have strength zero...?

 Thanks for any help, advice ....  :-)

 Piotrek