From owner-chemistry@ccl.net Fri Sep 23 00:22:34 2005 From: "CCL" To: CCL Subject: CCL: multi-reference CI Message-Id: <-29287-050922235305-10140-CFZb8NSgysV8KSsEUi7gNw---server.ccl.net> X-Original-From: Wai-To Chan Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=us-ascii Date: Thu, 22 Sep 2005 23:35:27 -0400 (EDT) MIME-Version: 1.0 Sent to CCL by: Wai-To Chan [chan---curl.gkcl.yorku.ca] --Replace strange characters with the "at" sign to recover email address--. <<<<<<< Hi Jeny, Molpro, Columbus, Gamess, NWChem. Cheers, Seth >>>>>>>>>>> If Gamess above refers to gamess-US can you point me to the specific input group described in INPUT.DOC where I can look up for the setup of a multi-reference CI job? I know gamess in a MCSCF calculation also includes a CAS-CI job step. To my understanding this is not MRCI. So maybe I am missing something or I am not using an updated version. Wai-To Chan From owner-chemistry@ccl.net Fri Sep 23 16:31:23 2005 From: "CCL" To: CCL Subject: CCL: W:problem with SCIPCM Message-Id: <-29288-050923161309-16103-aSoa4QPf/ap66Lrz+dczfg:-:server.ccl.net> X-Original-From: Jim Hess Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=ISO-8859-1; format=flowed Date: Fri, 23 Sep 2005 15:20:06 -0400 MIME-Version: 1.0 Sent to CCL by: Jim Hess [hess:-:gaussian.com] --Replace strange characters with the "at" sign to recover email address--. I cannot be certain of the reason for the error you received without seeing more output. My suspicion is that you are using an ECP basis set. Use of ECP basis sets with SCRF=SCIPCM is problematic and not recommended. If you are not using an ECP, this error can often be overcome by first converging the gas-phase wavefunction, then using "guess=read scf=novaracc" during the SCI-PCM calculation. More difficult cases can benefit from additional input. I am appending below my SCI-PCM frequently-asked-questions entry which will explain the available input. Regards, Jim Hess Q. My SCI-PCM calculations always crash with the error: WARNING! Serious error in surface integrals. It is probable that some of the solute is outside the cavity and/or parts of the cavity surface cannot be reached from the origin. Try more integration points or a different set of integration origins. Surface Problems in SciFoc How do I add more integration points? A. There are several possible causes for this error and not all solutions involve the use of additional integration points. 1) You are using an effective core potential basis set. The combination of an ecp basis set and scrf=scipcm is problematic and not recommended. There is no reliable workaround at this time. 2) You are using a revision of G98 prior to Rev. A.11 and therefore the default behavior is to scale the polarization charges. This procedure is problematic and is no longer the default in Rev. A.11 (or G03). To turn off scaling in earlier revisions requires some extra input on the same line as the dielectric constant and isodensity value. The following input is an example: #p pbe1pbe/6-31G* opt scrf=scipcm test ethene in dichloromethane 0 1 C C,1,CC H,1,CH,2,HCC H,1,CH,2,HCC,3,180.,0 H,2,CH,1,HCC,3,180.,0 H,2,CH,1,HCC,4,180.,0 CC=1.31477 CH=1.07363 HCC=121.8867 8.93 0.0004 302 1 3 F 0 The allowed values on the above line are summarized below: Input: Epsi Cont IPhi ITheta ISurf NoPrun IScal e.g. : 78.3 0.0004 40 20 3 F 0 --------------------------------------------------- Epsi = Dielectric constant of solvent Cont = Value of isodensity surface in atomic units. 0.0004 au is recommended and the default. IPhi = Number of phi values for numerical surface integration, or number of points in a Lebedev grid. Default is 302. ITheta = Number of theta Values for numerical surface integration, 1 to use a Lebedev grid, which is the default. ISurf = Whether to do surface integrals using a single origin (2) or piecewise, using Becke grids (3). 3 is most general and the default, but 2 is faster for convex cavities. NoPrun = Whether to not prune out close points in conductor scaled calculations. Default is False. Internally DoPrun = .not.NoPrun IScal = Whether to scale the polarization charges. 0=no. 1=yes, scale negative and positive charges separately and uniformly so that the total polarization charge equals -(1-1/epsi) times the charge of the solute molecule. This corresponds to localization of the solute charge distribution in the cavity. 2=yes, scale the polarization charges so that the TOTAL potential at all points on the cavity surface is zero when the medium is a conductor (epsi=infinity). Default is 2. Explicit derivatives of the scale factors are available for 0 and 2 only. 3) In some cases, this error does indeed mean that more integration points are necessary. To increase the number of integration points, change the values for IPhi and ITheta as described above. If you wish to use a Lebedev grid (the default), the allowed values of IPhi are 302, 434, 590, 770, and 974. The value of ITheta is always chosen as 1 when a Lebedev grid is desired. If you wish to use a general grid, choose any value for IPhi and ITheta. In cases 2 and 3 above, you should also consider using "scf=novaracc". This option uses full integral accuracy throughout the scf cycle procedure and can often aid in convergence. For cases which are exceptionally difficult to converge, it is often helpful to first converge the calculation with a diffuse isodensity value, for example 0.00004. After convergence is reached with the diffuse value, use this result as a guess for a calculation using a less diffuse isodensity. CCL wrote: >Sent to CCL by: "Soto Delia" [sotodelia;;hotmail.com] > >--Replace strange characters with the "at" sign to recover email address--. > >I need your help >I`m trying to make a optimization with SCIPCM but I have the next problem > >WARNING! Serious error in surface integrals. > Nuclear flux = 317.76 Qnuc = 336.00 Error in int = 0.00 > It is probable that some of the solute is outside the cavity and/or > parts of the cavity surface cannot be reached from the origin. > Try more integration points or a different set of integration origins. > > Surface Problems in SciFoc > Error termination via Lnk1e in /home/g03/l502.exe > >What I can do? Tanks >Delia >sotodelia:-:hotmail.com> > > > > >