From owner-chemistry@ccl.net Wed Aug 28 08:59:00 2013 From: "Ichraf Oueslati ichraf.oueslati(_)obspm.fr" To: CCL Subject: CCL: More than one imaginary frequencies Message-Id: <-49118-130828085650-5882-1uz/jOJurGVF/2q5chEdgQ ~ server.ccl.net> X-Original-From: "Ichraf Oueslati" Date: Wed, 28 Aug 2013 08:56:49 -0400 Sent to CCL by: "Ichraf Oueslati" [ichraf.oueslati : obspm.fr] Hi all, In order to find a Minimum Energy Path, I run an IRC calculation with G09. When the frequencies of the points along the path were computed, I found more than one imaginary frequencies for each one. I already started IRC calculation with an optimized TS which has one and only imaginary frequency. For optimisation, I started by using B3LYP method then MP2 method with ts and noeigen keyword. This optimized TS connects to the reactant and product (I checked the geometries). I thought that the points along the MEP must have only positive frequencies. Am I wrong ?? Did the reaction path founded by IRC algorithm is correct? Why did I get those negative frequencies for the points along the MEP? what should I do to fix this problem? From owner-chemistry@ccl.net Wed Aug 28 09:44:00 2013 From: "Thuy Phan phanthuyhtc^_^gmail.com" To: CCL Subject: CCL: magnetic moment of atom Message-Id: <-49119-130828054800-24982-+JmpxllNLHhvWsPOhbZeWQ,,server.ccl.net> X-Original-From: "Thuy Phan" Date: Wed, 28 Aug 2013 05:47:59 -0400 Sent to CCL by: "Thuy Phan" [phanthuyhtc]-[gmail.com] I want to add something further in this query- How to calculate particular orbital contribution to total magnetic moment or magnetic moment of the M atom and magnetic moment M of 3d, 4s and 4p states for M atom in MAgn cluster ? Hope to see you helpful suggestions.. Thanks very much. From owner-chemistry@ccl.net Wed Aug 28 10:34:00 2013 From: "Close, David M. CLOSED=mail.etsu.edu" To: CCL Subject: CCL: More than one imaginary frequencies Message-Id: <-49120-130828103219-27879-Ms/PdcpmMXkvKWOQtTzA7g/./server.ccl.net> X-Original-From: "Close, David M." Content-Language: en-US Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="us-ascii" Date: Wed, 28 Aug 2013 14:32:12 +0000 MIME-Version: 1.0 Sent to CCL by: "Close, David M." [CLOSED[*]mail.etsu.edu] Ichraf: You are right. But since you have more than on negative eigenvalue, you are not on a true TS. You are on a saddle point. You are however close to the answer. You have to cut out the coordinates and displace the geometry in the direction of the TS. Redo the calculation and you should arrive at the TS. There is a simple fortran program to perform this procedure. I can send it to you if you like. Regards, Dave Close. -----Original Message----- > From: owner-chemistry+closed==etsu.edu(0)ccl.net [mailto:owner-chemistry+closed==etsu.edu(0)ccl.net] On Behalf Of Ichraf Oueslati ichraf.oueslati(_)obspm.fr Sent: Wednesday, August 28, 2013 8:57 AM To: Close, David M. Subject: CCL: More than one imaginary frequencies Sent to CCL by: "Ichraf Oueslati" [ichraf.oueslati : obspm.fr] Hi all, In order to find a Minimum Energy Path, I run an IRC calculation with G09. When the frequencies of the points along the path were computed, I found more than one imaginary frequencies for each one. I already started IRC calculation with an optimized TS which has one and only imaginary frequency. For optimisation, I started by using B3LYP method then MP2 method with ts and noeigen keyword. This optimized TS connects to the reactant and product (I checked the geometries). I thought that the points along the MEP must have only positive frequencies. Am I wrong ?? Did the reaction path founded by IRC algorithm is correct? Why did I get those negative frequencies for the points along the MEP? what should I do to fix this problem?http://www.ccl.net/cgi-bin/ccl/send_ccl_messagehttp://www.ccl.net/chemistry/sub_unsub.shtmlhttp://www.ccl.net/spammers.txt