CCL: TDDFT for Large Unsaturated pi-Systems

 Sent to CCL by: "Igor Avilov" [avilovi|,|averell.umh.ac.be]
 Dear Sue,
 Some problems with DFT when dealing with large unsaturated pi-systems are
 described in the following article and references therein (see "extended
 delocalization" section).
 JEFFREY R. REIMERS, ZHENG-LI CAI, ANTE BILI, AND NOEL S. HUSH. "The
 Appropriateness of Density-Functional Theory for the Calculation of Molecular
 Electronics Properties" Ann. N.Y. Acad. Sci.
 1006: 235-251 (2003). doi: 10.1196/annals.1292.017
 Igor.
 -----Original Message-----
 > From: owner-chemistry^^^ccl.net [mailto:owner-chemistry^^^ccl.net]
 Sent: mardi 4 avril 2006 5:20
 To: Igor Avilov
 Subject: CCL: TDDFT for Large Unsaturated pi-Systems
 Sent to CCL by: "Sue  L" [chsue2004|-|yahoo.com]
 Does anyone know which DFT functional in TDDFT is suitable to calculate the
 singlet-singlet excitations for large unsaturated pi-systems? B3LYP usually
 underestimate the excitation energies for these systems
 Thank you very much
 Suehttp://www.ccl.net/cgi-bin/ccl/send_ccl_messagehttp-:-//www.ccl.net/chemistry/sub_unsub.shtmlhttp-:-//www.ccl.net/spammers.txt