From owner-nwchem-users@emsl.pnl.gov Thu Aug 24 08:44:52 2006 Received: from odyssey.emsl.pnl.gov (localhost [127.0.0.1]) by odyssey.emsl.pnl.gov (8.13.7/8.13.7) with ESMTP id k7OFipoc016616 for ; Thu, 24 Aug 2006 08:44:52 -0700 (PDT) Received: (from majordom@localhost) by odyssey.emsl.pnl.gov (8.13.7/8.13.7/Submit) id k7OFip58016615 for nwchem-users-outgoing-0915; Thu, 24 Aug 2006 08:44:51 -0700 (PDT) X-Authentication-Warning: odyssey.emsl.pnl.gov: majordom set sender to owner-nwchem-users@emsl.pnl.gov using -f X-IronPort-AV: i="4.08,165,1154934000"; d="scan'208"; a="4674557:sNHT35919583" X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Subject: RE: [NWCHEM] Optimization of excited state Date: Thu, 24 Aug 2006 08:44:47 -0700 Message-ID: In-Reply-To: <0c7d01c6c76b$d474a480$12624084@ch.huji.ac.il> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [NWCHEM] Optimization of excited state Thread-Index: AcbHbGLzw83PSechSwaEuFqekk4cBwAJd+tA From: "Kowalski, Karol" To: "David Danovich" , "nwchem-user" X-OriginalArrivalTime: 24 Aug 2006 15:44:49.0138 (UTC) FILETIME=[3B587D20:01C6C794] Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by odyssey.emsl.pnl.gov id k7OFioIm016612 Sender: owner-nwchem-users@emsl.pnl.gov Precedence: bulk Dear David, For excited-state calculations you should use the Equation-of-motion CC methods (EOMCC) (the use of the CCSD(T) approach in the context of excited states is rather problematic). For example, the input for EOMCCSD (EOMCC with singles and doubles) looks like this: TCE FREEZE ATOMIC CCSD NROOTS 2 TARGETSYM A2 END which means that you requested 2 excited states of a2 symmetry on the EOMCCSD level. Contrary to the CCSD(T) method, the symmetry of excited state in the EOMCCSD approach can be different from the symmetry of the reference function. Good luck, Karol -----Original Message----- From: owner-nwchem-developers@emsl.pnl.gov [mailto:owner-nwchem-developers@emsl.pnl.gov] On Behalf Of David Danovich Sent: Thursday, August 24, 2006 3:56 AM To: nwchem-user Subject: [NWCHEM] Optimization of excited state Hello, I am doing ROHF-CCSD(T) calculations of excited states using nwchem. Unfortunately I was not able to find how to do this in manual. Does it possible at all? If yes, could somebody explain me how to do this type of calculations? How can I lower symmetry of the system in CCSD(T) calculations? CCSD(T) can not use symmetry high than Abelian group. It means that if my system has D3h symmetry I have to lower it to c2v. The question is - can I use in geometry specification D3h symmetry and tell to program to use c2v symmetry in ccsd(t) calculation? Thank you David My input file below: start al3-opt memory heap 200 stack 200 global 600 mb geometry symmetry C1 Al 1.276269 -0.735208 0.000000 Al -1.274269 -0.737511 0.000000 Al 0.000000 1.473719 0.000000 end basis Al library cc-pvtz end SCF DOUBLET ROHF END TCE SCF io replicated tilesize 15 freeze atomic NROOTS 4 TARGET 1 CCSD(T) END TASK TCE OPTIMIZE ________________________________________________________________ Dr. David Danovich, Department of Organic Chemistry, The Hebrew University, Edmond J. Safra Campus - Givat Ram, 91904 Jerusalem, Israel http://yfaat.ch.huji.ac.il/david.html, david.danovich@huji.ac.il FAX:(+972)-2-6584033, Phone:(+972)-2-6586934(w), Mobile:(+972)-544-768669