From chemistry-request # - at - # server.ccl.net Fri Jul 21 17:35:02 2000 Received: from prserv.net (out2.prserv.net [32.97.166.32]) by server.ccl.net (8.8.7/8.8.7) with ESMTP id RAA16775 for ; Fri, 21 Jul 2000 17:35:01 -0400 From: jmmckel ^at^ attglobal.net Received: from attglobal.net ([32.101.203.137]) by prserv.net (out2) with SMTP id <200007212134092290306867e>; Fri, 21 Jul 2000 21:34:10 +0000 Message-ID: <3978C0E8.2E9F2BE6 ":at:" attglobal.net> Date: Fri, 21 Jul 2000 16:30:16 -0500 Reply-To: jmmckel-!at!-attglobal.net X-Mailer: Mozilla 4.51 [en]C-CCK-MCD (WinNT; I) X-Accept-Language: en MIME-Version: 1.0 To: Marcel Swart CC: CHEMISTRY-: at :-ccl.net Subject: Re: CCL:DFT & metal metal bonds References: <200007200722.JAA66801 #at# zisgi.unizh.ch> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit I recall using the relativistic ECP's in deMon [also in DGAUSS] for the Ag dimer. The 17 valence ECP was better than the 11 or 1 electron ECP's, and was better than all the all electron non-relativistic results. John McKelvey Marcel Swart wrote: > >You want to elaborate on this? Is it because of the STOs? As to GTO's I > >use TZVP/P basis sets, which are not too bad usually. > > Yes, the STO's are always much better. But not only that. It is a > very clever program, making the calculations very efficient when > looking at CPU-time, parallellization, those kind of things. > > > > Furthermore, did you also include relativistic effects ? > > > >yes, scalar relativistic via the ECP. > > Well, that's not really what I meant. You assume that the ECP's mimic > the relativistic effects you are after, but it is not the same as > including the relativistic effects themselves !!! > > > > I guess when you look at Tungsten/Molybdenum, these can be quite > >significant. > >> Again this is a YES to ADF, since in this program these effects are > > > easily taken into account. > > Also, I know from work from my Professor (yet unpublished I think), > who is an expert in Relativistic Quantum Chemistry (J.G. Snijders), > that these relativistic effects are needed for heavy atom dimers. If > you don't include them (properly), the calculations are not > performing very well. > > Marcel. > > -= This is automatically added to each message by mailing script =- > CHEMISTRY _-at-_)ccl.net -- To Everybody | CHEMISTRY-REQUEST _-at-_)ccl.net -- To Admins > MAILSERV -x- at -x- ccl.net -- HELP CHEMISTRY or HELP SEARCH > CHEMISTRY-SEARCH-!at!-ccl.net -- archive search | Gopher: gopher.ccl.net 70 > Ftp: ftp.ccl.net | WWW: http://www.ccl.net/chemistry/ | Jan: jkl /at\ccl.net