From owner-chemistry@ccl.net Fri Feb 14 11:58:01 2020 From: "Tian Lu sobereva^-^sina.com" To: CCL Subject: CCL: Isosurface representation of VSCC Message-Id: <-53975-200214090137-6310-kHFpkl7C2Iv+RIxPaBmfiw^server.ccl.net> X-Original-From: "Tian Lu" Date: Fri, 14 Feb 2020 09:01:35 -0500 Sent to CCL by: "Tian Lu" [sobereva-,-sina.com] Dear Tobias, You can use Multiwfn to calculate grid data of Laplacian of electron density and directly visualize its isosurface, see example in Section 4.5.2 of Multiwfn manual. Furthermore, if you want to obtain better graphical effect, you can export the grid data as cube file via corresponding option in post-process menu of Multiwfn, then you can use e.g. VMD and ChimeraX to render it as isosurface, as illustrated in Section 4.A.14 of Multiwfn manual and this video tutorial: https://youtu.be/vC48iEB8PwI, respectively. -------------------------------- Best regards, Dr. Tian Lu Beijing Kein Research Center for Natural Sciences, Beijing, P. R. China http://www.keinsci.com ----- Original Message ----- > From: "Tobias Kraemer tobias.kraemer]~[mu.ie" To: "Lu, Tian " Subject: CCL: Isosurface representation of VSCC Date: 2020-02-14 21:23 Sent to CCL by: "Tobias Kraemer" [tobias.kraemer*mu.ie] Dear all, I have a question for those of you with experience in QTAIM analysis, in particular the Laplacian topology. I have seen a number of of publications that showed isosurface representations of the Valence-Shell Charge Concentration (VSCC) regions around a specific atom (in a molecule), nicely highlighting bonding (bcc) and lonepair (nbcc) regions. One such example can be found in Stalke's paper Organometallics, 2008, 27, 2306. I have been playing around with some model systems and the AIMALL software, and whilst I was able to figure out how to perform a topological analysis of the Laplacian itself, it is not clear to me how to visualise these VSCC regions as envelope surfaces. As far as I understand this is not simply a 3D plot of the Laplacian (or L(rho) function), but I might be wrong. Could anybody give me some advise which programs can do this and how it is done? I'd be curious to learn this and appreciate your help. Kind regards, Tobias