From owner-chemistry@ccl.net Sun Jul 3 04:00:00 2011 From: "bonoit dahmani bonoit_10:_:yahoo.fr" To: CCL Subject: CCL: Re : CCL: Proton affinity Message-Id: <-45019-110703035225-20790-t8QEjXZjfcRKhjg80nmhXQ.@.server.ccl.net> X-Original-From: bonoit dahmani Content-Type: multipart/alternative; boundary="0-1108567725-1309679537=:70659" Date: Sun, 3 Jul 2011 08:52:17 +0100 (BST) MIME-Version: 1.0 Sent to CCL by: bonoit dahmani [bonoit_10:_:yahoo.fr] --0-1108567725-1309679537=:70659 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Dear Arsalane, It's=A0so easy, you calculate the energies of your compound and your proton= ated compound with the method of your choice and subtract them from each ot= her.=A0You can=A0use the thermodynamically corrected energies (enthalpies) = for that purpose. Sincerely, Bonoit =A0 --0-1108567725-1309679537=:70659 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable
Dear Arsalane,
It's so easy, you calculate the energies of your compound and you= r protonated compound with the method of your choice and subtract them from= each other. You can use the thermodynamically corrected energies= (enthalpies) for that purpose.

Sincerely,
Bonoit
 
--0-1108567725-1309679537=:70659-- From owner-chemistry@ccl.net Sun Jul 3 20:38:00 2011 From: "carlos navarro canavarro\a/alumnos.utalca.cl" To: CCL Subject: CCL: Transition state - hydrogen deprotonation Message-Id: <-45020-110703142545-21513-ABF2GAhZuZHbPu87plEQGA|*|server.ccl.net> X-Original-From: carlos navarro Content-Type: multipart/alternative; boundary="_2b8a97db-87c8-4c40-a4f2-9a62cd06e8cd_" Date: Sun, 3 Jul 2011 18:25:36 +0000 MIME-Version: 1.0 Sent to CCL by: carlos navarro [canavarro{=}alumnos.utalca.cl] --_2b8a97db-87c8-4c40-a4f2-9a62cd06e8cd_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi everyone: I'm working in a 2-steps transition state. The first step consist in the de= protonation of an alcohol by a water molecule and a hystidine=2C and then a= nucleophilic attack by this alcohol to an acetylCoA. The thing is i have o= nly one imaginary frequencie (-139) and i can see clearly that this frecuen= cie corresponds to the step i'm looking for (with gausview)=2C but when i w= ant to obtain the reactants and products (IRC) the search always goes to th= e reactants=2Ceither using forward or reverse as the keyword. I don't know = why=2C . I found this TS at PM3 level (Reactants: -209.38 kcal/mol TS: -158.16 kcal/= mol Products: -179.33 kcal/mol) These are the keywords i'm using now: # b3lyp/6-31g(d) scf=3D(tight=2Cdirect) int=3DUltrafinegrid irc=3D(calcfc= =2Cforward=2Cmaxpoint=3D150=2Cstepsize=3D5) geom=3Dconnectivity What could i do? i hope you can help me. Cheers. ps- Sorry if my english is not perfect. = --_2b8a97db-87c8-4c40-a4f2-9a62cd06e8cd_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hi everyone:
I'm working in a 2-steps transition state. The first step c= onsist in the deprotonation of an alcohol by a water molecule and a hystidi= ne=2C and then a nucleophilic attack by this alcohol to an acetylCoA. The t= hing is i have only one imaginary frequencie (-139) and i can see clearly t= hat this frecuencie corresponds to the step i'm looking for (with gausview)= =2C but when i want to obtain the reactants and products (IRC) the search a= lways goes to the reactants=2Ceither using forward or reverse as the keywor= d. I don't know why=2C .
I found this TS at PM3 level (Reactants: -209.3= 8 kcal/mol TS: -158.16 kcal/mol Products: -179.33 kcal/mol)
These are th= e keywords i'm using now:
# b3lyp/6-31g(d) scf=3D(tight=2Cdirect) int=3D= Ultrafinegrid irc=3D(calcfc=2Cforward=2Cmaxpoint=3D150=2Cstepsize=3D5) geom= =3Dconnectivity
What could i do?
i hope you can help me.

Cheer= s.
ps- Sorry if my english is not perfect.
= --_2b8a97db-87c8-4c40-a4f2-9a62cd06e8cd_--