From owner-chemistry@ccl.net Sat Oct 27 14:24:01 2018 From: "=?UTF-8?Q?Jan_G=c3=b6tze?= jgoetze[]zedat.fu-berlin.de" To: CCL Subject: CCL:G: Low-progression Franck-Condon transitions Message-Id: <-53530-181027112536-4683-MKqyVDvBb2Ze/bMvKgkMDw.:.server.ccl.net> X-Original-From: =?UTF-8?Q?Jan_G=c3=b6tze?= Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=utf-8; format=flowed Date: Sat, 27 Oct 2018 17:25:23 +0200 MIME-Version: 1.0 Sent to CCL by: =?UTF-8?Q?Jan_G=c3=b6tze?= [jgoetze##zedat.fu-berlin.de] Dear Tobias, the data you provided only allow for limited analysis why your proble occurs. In case you did not do any errors in preparation of your two excited states, it appears that the minima of ground and excited state are very distant from each other (such as groups rotating, and/or normal modes differing strongly between ground and excited state). For a large, planar, aromatic system like pc this is rather unusual. As such, without further details on the molecular structure, any additional help can only be guesswork. To obtain a preliminary spectrum quickly and often without problems, I personally would suggest using a vertical TD approach, which might be available in Gaussian16, or an IMDHO-FA as in ORCA. See for example doi:10.1021/ct500830a Cheers, Jan Am 26.10.2018 um 12:57 schrieb Tobias Kraemer tobias.kraemer[a]mu.ie: > Sent to CCL by: "Tobias Kraemer" [tobias.kraemer_._mu.ie] > Hello everyone, > > I am interested in calculating vibrationally-resolved spectra in G16. The > molecule in question is a phthalocyanine (pc) complex. I've followed the > protocol detailed in the whitepaper by Barone et al., however in the > final step (generating the spectrum) an error occurs: > > > ================================================== > Calculations of Band Intensities > ================================================== > > -- To: vibronic fundamental state -- > Spectrum progression: 0.06% > > -- To: single overtones -- > Spectrum progression: 0.71% > > -- To: combinations of 2 simultaneously excited modes -- > Spectrum progression: 4.14% > > ERROR: Low progression after class 2. Total convergence = 4.1%. > The vibronic spectrum will likely be unreliable. Stopping. > > The whitepaper provides some possible causes, but I'd like to ask for > some expert opinions here on CCL nonetheless. In the excited state > optimisation I have included 6 states, of which the gradients for the > first one are to be followed [TD=(Read,NStates=6,Root=1)]. > There are a good number of keywords listed on the Gaussian16 webpage that > relate to this type of calculation, and I'd appreciate some guidance on > the above issue and possible ways around it. > > Thanks for your help, as always much appreciated. > > Kind regards, > > Tobias From owner-chemistry@ccl.net Sat Oct 27 19:19:00 2018 From: "Stefano Guglielmo stefano.guglielmo- -unito.it" To: CCL Subject: CCL: tinker integration timestep Message-Id: <-53531-181027190441-5715-9zjFkHWnHDCoGJUfCmOMpw###server.ccl.net> X-Original-From: "Stefano Guglielmo" Date: Sat, 27 Oct 2018 19:04:40 -0400 Sent to CCL by: "Stefano Guglielmo" [stefano.guglielmo*|*unito.it] Dear all, maybe this is a trivial question, but I would like to know if it is possible to set different integration timesteps for intra- and intermolecular interactions in tinker. Thanks in advance Stefano