From owner-chemistry@ccl.net Fri Oct 17 03:55:00 2014 From: "Sergio Manzetti sergio.manzetti-.-outlook.com" To: CCL Subject: CCL: Question on symmetry Message-Id: <-50596-141017035321-27209-j9VzQDQ0EKdLnWp51kBV4w(0)server.ccl.net> X-Original-From: "Sergio Manzetti" Date: Fri, 17 Oct 2014 03:53:20 -0400 Sent to CCL by: "Sergio Manzetti" [sergio.manzetti\a/outlook.com] Thanks Mariusz. This was a clear answer. So a D2h, the Oxygen molecules for instance, has the following set of symmetry operations: E, C2, C_phi, sigma_xz, sigma_yz, and i. That is, a total number of dimensions, h = 6 ? Thanks! Sergio Sent to CCL by: Mariusz Radon [mariusz.radon%gmail.com] On 10/16/2014 08:14 PM, Sergio Manzetti sergio.manzetti..outlook.com wrote: > My simple question was: > > If one has the D_inf_h, is > > C_inf an actual operation, such as C2? > > Thanks Dear Sergio: As far as I understand your question, you are confused by the strange notation "C_inf" used, indeed, in some character tables. In this context "C_inf" means a rotation by an angle phi, where 0 < phi < 2*pi. The inverse of this rotation, i.e., the rotation by angle -phi, belongs to the same class (=> it has the same character in all the irreps). Therefore, in character tables, this class of symmetry operations (C_phi, C^{-1}_phi) is usually denoted as "2C_inf" or "2C_phi" (I prefer the second notation). Hope that this will be useful. All the best, Mariusz -- Dr Mariusz Radon, Ph.D. Coordination Chemistry Group Faculty of Chemistry Jagiellonian University ul. Ingardena 3, 30-060 Krakow, Poland http://www2.chemia.uj.edu.pl/~mradon From owner-chemistry@ccl.net Fri Oct 17 13:22:01 2014 From: "Abrash, Samuel sabrash]_[richmond.edu" To: CCL Subject: CCL: Question on symmetry Message-Id: <-50597-141017132024-30887-Dz/DSR6zbs1p1wuH+j+Abw{=}server.ccl.net> X-Original-From: "Abrash, Samuel" Content-Language: en-US Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="us-ascii" Date: Fri, 17 Oct 2014 17:20:16 +0000 MIME-Version: 1.0 Sent to CCL by: "Abrash, Samuel" [sabrash() richmond.edu] There's an excellent yet easy book on group theory that's easy to learn from and provides a solid foundation in the most important techniques. It's called Molecular Symmetry and Group Theory, by Vincent, published by Wiley. Sent from my iPhone > On Oct 17, 2014, at 4:31 AM, Sergio Manzetti sergio.manzetti-.-outlook.com wrote: > > > Sent to CCL by: "Sergio Manzetti" [sergio.manzetti\a/outlook.com] > Thanks Mariusz. This was a clear answer. > > So a D2h, the Oxygen molecules for instance, has the following set of symmetry operations: > > E, C2, C_phi, sigma_xz, sigma_yz, and i. > > That is, a total number of dimensions, h = 6 ? > > Thanks! > > Sergio > > Sent to CCL by: Mariusz Radon [mariusz.radon%gmail.com] >> On 10/16/2014 08:14 PM, Sergio Manzetti sergio.manzetti..outlook.com wrote: >> My simple question was: >> >> If one has the D_inf_h, is >> >> C_inf an actual operation, such as C2? >> >> Thanks > > Dear Sergio: > > As far as I understand your question, you are confused by the strange > notation "C_inf" used, indeed, in some character tables. > > In this context "C_inf" means a rotation by an angle phi, where 0 < phi > < 2*pi. > > The inverse of this rotation, i.e., the rotation by angle -phi, belongs > to the same class (=> it has the same character in all the irreps). > Therefore, in character tables, this class of symmetry operations > (C_phi, C^{-1}_phi) is usually denoted as "2C_inf" or "2C_phi" (I prefer > the second notation). > > Hope that this will be useful. > > All the best, > Mariusz > > > > -- > Dr Mariusz Radon, Ph.D. > Coordination Chemistry Group > Faculty of Chemistry > Jagiellonian University > ul. Ingardena 3, 30-060 Krakow, Poland > http://www2.chemia.uj.edu.pl/~mradon> > From owner-chemistry@ccl.net Fri Oct 17 15:22:01 2014 From: "Thomas Manz tmanz{=}nmsu.edu" To: CCL Subject: CCL: computational patent examples Message-Id: <-50598-141017135956-11608-CXsmfGHwDXDZlOVBfyXXXg(~)server.ccl.net> X-Original-From: Thomas Manz Content-Type: multipart/alternative; boundary=001a11c13e4aa735d70505a22196 Date: Fri, 17 Oct 2014 11:59:50 -0600 MIME-Version: 1.0 Sent to CCL by: Thomas Manz [tmanz_+_nmsu.edu] --001a11c13e4aa735d70505a22196 Content-Type: text/plain; charset=UTF-8 Hi, I am wondering whether anyone has heard of a U.S. Patent being filed for a newly proposed chemical process and/or new chemical compound or catalyst on the basis of purely computational chemistry research with no experimental data at the time of patent filing? If so, could anyone provide a few examples? If experiments were performed only after the patent was filed (for example, during or after the examination period), those would still count as examples. This question has come up in my research and I would be grateful for any examples that could be provided. Sincerely, Tom --001a11c13e4aa735d70505a22196 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Hi,

I am wondering whether anyone has h= eard of a U.S. Patent being filed for a newly proposed chemical process and= /or new chemical compound or catalyst on the basis of purely computational = chemistry research with no experimental data at the time of patent filing?<= /div>

If so, could anyone provide a few examples?=C2=A0= =C2=A0If experiments were performed only after the patent was filed (for ex= ample, during or after the examination period), those would still count as = examples. This question has come up in my research and I would be grateful = for any examples that could be provided.

Sincerely= ,

Tom
--001a11c13e4aa735d70505a22196-- From owner-chemistry@ccl.net Fri Oct 17 18:32:01 2014 From: "Jay Whitfield jdwhitfield|a|gmail.com" To: CCL Subject: CCL: Re. Symmetry question Message-Id: <-50599-141016143553-27024-kpuxACbBAwFSloVFhEhSwQ#server.ccl.net> X-Original-From: Jay Whitfield Content-Type: text/plain; charset=UTF-8 Date: Thu, 16 Oct 2014 20:35:43 +0200 Mime-Version: 1.0 (1.0) Sent to CCL by: Jay Whitfield [jdwhitfield++gmail.com] Hi Sergio, The group and its representation are different. If you have a pen nearby, it carries a representation of C_inf. In order to deal with continuous groups like C_inf you need to refer back to your knowledge of angular momentum. In fact the azimuthal part of the spherical harmonics also carry a representation of C_inf. Again, you really need to go to the library to brush up on the basic terminology. Another book you might find useful is Schatz and Ratner "Quantum Mechanics in Chemistry" Dr. J. D. Whitfield VCQ Postdoctoral Fellow Vienna Center for Quantum Science and Technology email: james.whitfield(a)univie.ac.at web: homepage.univie.ac.at/james.whitfield > On Oct 16, 2014, at 20:28, Sergio Manzetti sergio.manzetti#%#outlook.com wrote: > > > Sent to CCL by: "Sergio Manzetti" [sergio.manzetti(!)outlook.com] > Thanks, so if one lists up the representations for the elements, one gets one vector representation for the C_inf, or infinitely many? > > This was no easy to see either on the page referred. > > Thanks > > > >> From: owner-chemistry%ccl.net >> To: sergio.manzetti%gmx.com >> Subject: CCL: Question on symmetry >> Date: Thu, 16 Oct 2014 16:19:50 +0300 >> >> >> Sent to CCL by: berger{}chem.helsinki.fi >> Hello, >> >>> Conversely in relation to O2 molecule, belonging to the point group >>> D_inf_h, it has these representations: >>> >>> E >>> C2 >>> 1 x sigma_v >>> 1 x sigma_h >>> 1 x sigma_d >>> 1 x i >> >> These are not representations but symmetry elements. >> >> But what you are searching for is probably this: >> >> http://www.webqc.org/symmetrypointgroup-d_h.html >> >> Cheers >> RB >> >>> However, the cyclic representation C_inf is not added here, on purpose, as >>> I wonder if it is a representation for this particular group (as inf is >>> infinite)? >>> >>> Thanks> >