From owner-chemistry@ccl.net Mon Jun 2 14:28:00 2014 From: "Chang, Christopher Christopher.Chang_._nrel.gov" To: CCL Subject: CCL: DFT14poll Message-Id: <-50144-140602121530-4730-LJgLj/7dwXr1ZdmbYo8ROw:server.ccl.net> X-Original-From: "Chang, Christopher" Content-Language: en-US Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="utf-8" Date: Mon, 2 Jun 2014 10:15:19 -0600 MIME-Version: 1.0 Sent to CCL by: "Chang, Christopher" [Christopher.Chang^nrel.gov] Appeals to authority are also dangerous. Why should we not weight Drs. Molt's and Bartlett's opinions equally? If the opinions are grounded in evidence and logic, then the opinion is only a convenient proxy for that deeper and more meaningful evidence and logic. The value of opinion polls is highly dependent on their intended usage. The first poll example on spherical harmonics would be perfectly respectable as an entrance/exit contrast poll for students. The second is probably run in the theoretical physics community among people whose lives revolve around the precision and accuracy of Planck's constant. Nonetheless, I do hope that the poll publication will include some language about intent (and conversely, poor uses of such information). I really like Dr. Rzepa's idea of categorization by a controlled vocabulary of physical chemical phenomena. The results could serve as a nice starting point for answering questions re: DF vs. property I see on the list. - CHC -----Original Message----- > From: owner-chemistry+christopher.chang==nrel.gov-x-ccl.net [mailto:owner-chemistry+christopher.chang==nrel.gov-x-ccl.net] On Behalf Of Robert Molt Jr r.molt.chemical.physics!=!gmail.com Sent: Sunday, June 01, 2014 1:07 PM To: Chang, Christopher Subject: CCL: DFT14poll Sent to CCL by: Robert Molt Jr [r.molt.chemical.physics]_[gmail.com] Sirs and Madames: A "popularity contest" is anathema to science. The world should not weight the opinion of Rodney Bartlett and Robert Molt equally in coupled cluster theory. Perhaps we should take a poll on what people think the first spherical harmonic is? Or take a poll on whether Planck's constant is too small? Evidence and and logic drive science. -Robert Molt On 06/01/2014 12:26 PM, Víctor Luaña Cabal victor,fluor.quimica.uniovi.es wrote: > Sent to CCL by: =?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal > [victor-.-fluor.quimica.uniovi.es] > On Sun, Jun 01, 2014 at 06:01:52AM +0000, Rzepa, Henry S h.rzepa:imperial.ac.uk wrote: >> Can I suggest that in future this poll be extended to indicate WHY any person indicates they LIKE a functional? As we all know, the choice of functional so often depends on what the property of interest is. >> >> I suggest initially a relatively short controlled list of properties, >> which can then be extended by “crowd sourcing”. Properties I have >> in mind might be eg >> >> 1. Reaction barriers >> 2. Normal mode analysis >> 3. Chiroptical properties >> 4. Hydrogen bonds >> 5. Excitation energies >> 6. Main group elements >> 7. Transition metals >> 8. Relativistic elements >> 9. NMR shieldings, NMR couplings >> 10. etc >> >> That way, we could find out eg the most liked functional for eg >> looking at hydrogen bonds. That would be enormously helpful to >> anyone looking to study eg hydrogen bonds. > Dear Prof. Rzepa, > > I have a deep respect for your work, that I use to love, but in this > case I dislike strongly the idea of deciding the use of a functional > by popularity. There are plenty of examples in which the most popular > route was not the best, just the easiest. It took decades, in many > cases, to turn back wrong but popular decisions. Two candidates should > be advised to create a safe road: the easiest AND the the best > founded. Notice that the most popular is not in my list. Popularity > can be obtained by well studied techniques that have nothing to do > with any real measurement of quality. > > As for your list of properties it is very useful and I will keep it > carefully. > > Best regards, > Dr. Víctor Luaña > > -- > \|/ > |^.^| > +---!OO--\_/--OO!------------------------------+---------------------- > +- > ! Dr.Víctor Luaña ! > ! Departamento de Química Física y Analítica ! > ! Universidad de Oviedo, 33006-Oviedo, Spain ! > ! e-mail: victor*fluor.quimica.uniovi.es ! > ! phone: +34-985-103491 fax: +34-985-103125 ! > +----------------------------------------------+ > GroupPage : http://azufre.quimica.uniovi.es/ (being reworked)http://www.ccl.net/cgi-bin/ccl/send_ccl_messagehttp://www.ccl.net/chemistry/sub_unsub.shtmlhttp://www.ccl.net/spammers.txt