From owner-chemistry@ccl.net Tue Oct 28 08:01:01 2008 From: "=?ISO-8859-1?Q?Tom=E1s_Pe=F1a_Ruiz?= truiz(a)ujaen.es" To: CCL Subject: CCL:G: global minimum Message-Id: <-37986-081028074442-4704-O7XG1NDYSKCLmqnD4fNlVQ[]server.ccl.net> X-Original-From: =?ISO-8859-1?Q?Tom=E1s_Pe=F1a_Ruiz?= Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=ISO-8859-1; format=flowed Date: Tue, 28 Oct 2008 11:45:29 +0100 MIME-Version: 1.0 Sent to CCL by: =?ISO-8859-1?Q?Tom=E1s_Pe=F1a_Ruiz?= [truiz!=!ujaen.es] Hi If your system is a linear molecule or has some linear section you can explore the pontential energy hypersurface by rotation of the main torsion angles, i.e., if you have something like that: Z-X-Y-J, it is posible to perfomr an scan around the X-Y bond. Approximated input: # opt(z-matrix) method/basis-set /'other options (scf, integral, etc.)'/ test comment line charge , multiplicity z-matrix (start) ..... Z d X a Y t J ..... z-matrix (end) Geometrical parameters (start) .... t=/starting value /S /number_of_steps/ /step_length /(example: S 18 10., makes a 180º degrees scan in 18 steps of 10º degrees) /.... /Geometrical parameters (end) Tomás nadia boutabba n_boutabba__yahoo.fr escribió: >Sent to CCL by: "nadia boutabba" [n_boutabba|,|yahoo.fr] >Dear ccl members, >i optimize a small molecule, i need to calculate its dissociation energy by different dft method >how to obtain a minimum? i would say how to be sure that i have a minimum.after the optimization i calculated the freq job and all frequencies are real, in low frequencies there is six near zero. >may be i need the global minimum of the molecule, i see in the ccl forum that this is possible by applying the simulated annealing method ( deterministic for small molecule). but i did not find any input gaussian example dealing with this? any help? thank you very much> > > > > From owner-chemistry@ccl.net Tue Oct 28 12:10:01 2008 From: "=?ISO-8859-2?Q?Pawe=B3_Panek?= flemsky{=}gmail.com" To: CCL Subject: CCL: global minimum Message-Id: <-37987-081028094044-7644-m3s89A4AO6zSXjQVF+3R5g:server.ccl.net> X-Original-From: "=?ISO-8859-2?Q?Pawe=B3_Panek?=" Content-Disposition: inline Content-Transfer-Encoding: base64 Content-Type: text/plain; charset=ISO-8859-2 Date: Tue, 28 Oct 2008 14:40:29 +0100 MIME-Version: 1.0 Sent to CCL by: "=?ISO-8859-2?Q?Pawe=B3_Panek?=" [flemsky%a%gmail.com] RGVhciBOYWRpYSwKCnlvdSBjYW4gdHJ5IEdhdXNzaWFuIGtleXdvcmQgb3B0PXRpZ2h0IG9yIGV2 ZW4gb3B0PXZlcnl0aWdodAooaHR0cDovL3d3dy5nYXVzc2lhbi5jb20vZ191ci9rX29wdC5odG0p LiBUaGlzIHdpbGwgbGV0IHlvdSBnZXQgYQpiZXR0ZXIgYXBwcm94aW1hdGlvbi4gQXMgc29tZWJv ZHkgd3JvdGUsIHlvdSBjYW4gZG8gYSBQRVMgc2NhbiwgYnV0IGl0CnNlZW1zIHRvIGJlIHF1aXRl IGRpZmZpY3VsdCB3YXkgdG8gYWNoaWV2ZSB0aGUgb3B0aW1pemVkIHN0cnVjdHVyZS4KClAuUy4g SSBkb24ndCBmZWVsIGFuIGV4cGVydCwgYnV0IEknbSBub3Qgc3VyZSBpZiB3ZSBzaG91bGQgdGFs ayBhYm91dApnbG9iYWwgbWluaW11bSAoZS5nLiBkdWUgdG8gdGhlIHZhcmlhdGlvbmFsIHByaW5j aXBsZSkuIEkgd2FzIGxlYXJudCwKdGhhdCB3ZSBjYW4gdGFsayBhYm91dCBtaW5pbXVtIGFuZCBv cHRpbWl6ZWQgc3RydWN0dXJlLCB3aGF0IHdlIGdldCBpcwpqdXN0IGJldHRlciBvciB3b3JzZSBh cHByb3hpbWF0aW9uIG9mIHRoZSBncm91bmQgc3RhdGUuCgotLSAKQmVzdCByZWdhcmRzLApQYXdl syBQYW5layAgICAgICAgbWFpbHRvOmZsZW1za3lAZ21haWwuY29tCg==