CCL: DFT14poll

"Information on WHY and for which applications specific functionals are
most useful are valuable, as are statistics on the number of PAPERS
(rather than the number of people) "liking" a functional, but these data
are best left to serious reviews."

Indeed, one could conceive of a number of review papers growing out of a comparison between the results of this survey ("What do researchers believe are the strengths of various functional?") and benchmark studies ("How do various functionals actually perform in their popularly believed areas of strength?") ÂKruse, Goerigk & Grimme (2012)Â[doi:10.1021/jo302156p]Âcomes to mind as a recent example. ÂSuch reviews would dabble a bit in the sociology of the matter, but could perhaps still be helpful in guiding the science toward increased rigor.



Brian Skinn
PhD, Chemical Engineering, MIT





On Mon, Jun 2, 2014 at 7:45 AM, N. Sukumar nagams-x-rpi.edu <owner-chemistry-*-ccl.net> wrote:

Sent to CCL by: "N. Sukumar" [nagams__rpi.edu]
"A popularity contest is anathema to science... Evidence and and logic
drive science."

In principle, yes. But important hiring and promotion decisions are often
based at least in part on citation statistics and impact factors.

I see this popularity contest on DFT functionals as no more than a social
media tool such as "what are your colleagues reading these days?"
Attempts to bias the results by multiple or robotic voting are misguided,
as are efforts to read more meaning into these "popularity" data.

Information on WHY and for which applications specific functionals are
most useful are valuable, as are statistics on the number of PAPERS
(rather than the number of people) "liking" a functional, but these data
are best left to serious reviews.

N. Sukumar
Professor of Chemistry
Shiv Nadar University, India
----------------------------
"Pursue something so important that even if you fail, the world is better
off with you having tried." -- Tim O'Reilly
http://as.wiley.com/WileyCDA/WileyTitle/productCd-0470769009.html
==============Original message text===============
On Sun, 01 Jun 2014 15:07:06 EDT "Robert Molt Jr
r.molt.chemical.physics!=!gmail.com" wrote:


Sent to CCL by: Robert Molt Jr [r.molt.chemical.physics]_[gmail.com]
Sirs and Madames:

A "popularity contest" is anathema to science. ÂThe 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? ÂOr 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, VÃctor LuaÃa 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 ÂI suggest that in future this poll be extended to indicate WHY
any person indicates they ÂLIKE Âa 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 Ââcrowd sourcingâ. Properties ÂI 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. ÂThat 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,
> Â Â Â Â Â Â Â Dr. VÃctor LuaÃa
>
> --
> Â Â Â Â Â \|/
> Â Â Â Â Â|^.^|
> +---!OO--\_/--OO!------------------------------+-----------------------
> !      ÂDr.VÃctor LuaÃa          !
> ! Departamento de QuÃmica FÃsica y AnalÃtica  !
> ! Universidad de Oviedo, 33006-Oviedo, Spain  !
> ! e-mail:  victor*fluor.quimica.uniovi.es   !
> ! phone: +34-985-103491 Âfax: +34-985-103125 Â !
> +----------------------------------------------+
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