From owner-chemistry(+ at +)ccl.net Mon Jun 2 18:06:00 2014 From: "Steven Bachrach sbachrac]|[trinity.edu" To: CCL Subject: CCL: DFT14poll Message-Id: <-50147-140602163835-18985-S20erQOBbBT8bfgjsMDaWA^^^server.ccl.net> X-Original-From: Steven Bachrach Content-Type: multipart/alternative; boundary=047d7b6dc67aad7c3604fae0607d Date: Mon, 2 Jun 2014 15:38:28 -0500 MIME-Version: 1.0 Sent to CCL by: Steven Bachrach [sbachrac(a)trinity.edu] --047d7b6dc67aad7c3604fae0607d Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable I also think the poll has value in discerning trends, especially new funtionals to appear on the list and ones that have fallen down or off. Steven On Mon, Jun 2, 2014 at 9:17 AM, Abrash, Samuel sabrash!^!richmond.edu < owner-chemistry]=[ccl.net> wrote: > > Sent to CCL by: "Abrash, Samuel" [sabrash..richmond.edu] > I think people are taking the words "popularity contest" too seriously. > It's just a poll to find out what members of this listserve, who are > mostly computational chemistry professionals, are using. I agree that th= e > absence of "why" makes this somewhat less useful. However, I think it's > useful because if I see a functional that I don't know about used widely, > I'm going to investigate it. (Note not blindly use it, but investigate > it.) Still the why is a useful bit of information. For example, I use > M062X for many of my calculations now, and if asked why, I'd say "because > reviewers insisted that it's better for complexes than PBEPBE even though > my results come out the same with either functional, and I wanted my pape= r > published." > > Best, > Sam > > -----Original Message----- > > From: owner-chemistry+sabrash=3D=3Drichmond.edu . ccl.net [mailto: > owner-chemistry+sabrash=3D=3Drichmond.edu . ccl.net] On Behalf Of Laidig, > Bill laidig.wd(_)pg.com > Sent: Sunday, June 01, 2014 8:45 PM > To: Abrash, Samuel > Subject: CCL: DFT14poll > > > Sent to CCL by: "Laidig, Bill" [laidig.wd=3Dpg.com] I strongly disagree > with this position. There are many scientifically valid reasons to know > which functionals are most popular among theoretical and computational > chemists (who, I am assuming, are the bulk of this mailing list). For > example: > > 1. Even if a functional is clearly inferior to another, if it is used muc= h > more in real calculations then there may be several reasons to use the > inferior function: > a. It is likely more widely implemented meaning you have a wider > choice of programs > to use and ways to validate that the calculations were performe= d > correctly. > b. Wider use means that there is a larger statistical pool of data > for assessing accuracy, > etc. This is often much more important than using a marginally > better method. We > see this in the long-term popularity of methods such as HF/3-21G= , > and B3LYP/6-31G*. > 2. Highly accurate, but arcane theoretical methods make communication of > results difficult outside the expert community as the reader has little > basis for assessing the quality of results. I learned this the hard way = in > my career in industry. > > Most users of computational chemistry want to know what small handful of > methods can be applied broadly to large classes of problems. As experts, > we are the group that is defining the next generation of standard methods > so I find it very useful to know in what directions we are heading. > Learning why we are using functionals can also let the developer of the > "next big thing" know when their efforts to publicize and promote their > methodology has fallen short and inspire them to better efforts in the > future. > > Bill Laidig > > -----Original Message----- > > From: owner-chemistry+laidig.wd=3D=3Dpg.com^ccl.net > > [mailto:owner-chemistry+laidig.wd=3D=3Dpg.com^ccl.net] On Behalf Of Rob= ert > > Molt Jr r.molt.chemical.physics!=3D!gmail.com > Sent: Sunday, June 01, 2014 3:07 PM > To: Laidig, Bill > 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, V=C3=ADctor Lua=C3=B1a Cabal victor,fluor.quimica= .uniovi.es > wrote: > > Sent to CCL by: =3D?iso-8859-1?Q?V=3DEDctor_Lua=3DF1a?=3D 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 an= y > 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 =E2=80=9Ccrowd sourcing=E2=80=9D. Prope= rties 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. V=C3=ADctor Lua=C3=B1a > > > > -- > > \|/ > > |^.^| > > +---!OO--\_/--OO!------------------------------+---------------------- > > +- > > ! Dr.V=C3=ADctor Lua=C3=B1a ! > > ! Departamento de Qu=C3=ADmica F=C3=ADsica y Anal=C3=ADtica ! > > ! 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.txthttp://www.ccl.net/cgi-bin/ccl/send_ccl_messageht= tp://www.ccl.net/chemistry/sub_unsub.shtmlhttp://www.ccl.net/spammers.txt > > > -=3D This is automatically added to each message by the mailing script = =3D-> > > --=20 Steven Bachrach Semmes Distinguished Professor and Assistant VP for Special Projects Department of Chemistry Trinity University Phone: 210-999-7379 1 Trinity Place Fax: 210-999-7569 San Antonio, TX 78212 email: sbachrach]=[trinity.edu --047d7b6dc67aad7c3604fae0607d Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
I also think the poll has value in discerning trends,= especially new funtionals to appear on the list and ones that have fallen = down or off.

Steven

On Mon, Jun 2, 2014 at 9:17 AM, Abrash, Samuel s= abrash!^!richmond.edu <owner-che= mistry]=[ccl.net> wrote:

Sent to CCL by: "Abrash, Samuel" [sabrash..richmond.edu]
I think people are taking the words "popularity contest" too seri= ously. =C2=A0It's just a poll to find out what members of this listserv= e, who are mostly computational chemistry professionals, are using. =C2=A0I= agree that the absence of "why" makes this somewhat less useful.= =C2=A0However, I think it's useful because if I see a functional that = I don't know about used widely, I'm going to investigate it. =C2=A0= (Note not blindly use it, but investigate it.) =C2=A0Still the why is a use= ful bit of information. =C2=A0For =C2=A0example, I use M062X for many of my= calculations now, and if asked why, I'd say "because reviewers in= sisted that it's better for complexes than PBEPBE even though my result= s come out the same with either functional, and I wanted my paper published= ."

Best,
Sam

-----Original Message-----
> From: owner-chemistry+sabrash=3D=3Drichmond.edu . ccl.net [mailto:owner-= chemistry+sabrash=3D=3Drichmond.edu . ccl.net] On Behalf Of Laidig, Bill laidig.wd(_)pg.com
Sent: Sunday, June 01, 2014 8:45 PM
To: Abrash, Samuel
Subject: CCL: DFT14poll


Sent to CCL by: "Laidig, Bill" [laidig.wd=3Dpg.com] I strongly disagree with this position. = =C2=A0There are many scientifically valid reasons to know which functionals= are most popular among theoretical and computational chemists (who, I am a= ssuming, are the bulk of this mailing list). =C2=A0For example:

1. Even if a functional is clearly inferior to another, if it is used much = more in real calculations then there may be several reasons to use the infe= rior function:
=C2=A0 =C2=A0 =C2=A0a. It is likely more widely implemented meaning you hav= e a wider choice of programs
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0to use and ways to validate that the calc= ulations were =C2=A0performed correctly.
=C2=A0 =C2=A0 =C2=A0b. Wider use means that there is a larger statistical p= ool of data for assessing accuracy,
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0etc. =C2=A0This is often much more import= ant than using a marginally better method. =C2=A0We
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0see this in the long-term popularity of m= ethods such as HF/3-21G, and B3LYP/6-31G*.
2. Highly accurate, but arcane theoretical methods make communication of re= sults difficult outside the expert community as the reader has little basis= for assessing the quality of results. =C2=A0I learned this the hard way in= my career in industry.

Most users of computational chemistry want to know what small handful of me= thods can be applied broadly to large classes of problems. =C2=A0As experts= , we are the group that is defining the next generation of standard methods= so I find it very useful to know in what directions we are heading. =C2=A0= Learning why we are using functionals can also let the developer of the &qu= ot;next big thing" know when their efforts to publicize and promote th= eir methodology has fallen short =C2=A0and inspire them to better efforts i= n the future.

Bill Laidig

-----Original Message-----
> From: owner-chemistry+laidig.wd=3D=3Dpg.com^ccl.net=
> [mailto:owner-chemistry= +laidig.wd=3D=3Dpg.com^= ccl.net] On Behalf Of Robe= rt
> Molt Jr r.molt.chemical.physics!=3D!gmail.com
Sent: Sunday, June 01, 2014 3:07 PM
To: Laidig, Bill
Subject: CCL: DFT14poll


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

A "popularity contest" is anathema to science. =C2=A0The world sh= ould not weight the opinion of Rodney Bartlett and Robert Molt equally in c= oupled cluster theory.

Perhaps we should take a poll on what people think the first spherical harm= onic is? =C2=A0Or 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, V=C3=ADctor Lua=C3=B1a Cabal victor,fluor.quimica.uniovi.es w= rote:
> Sent to CCL by: =3D?iso-8859-1?Q?V=3DEDctor_Lua=3DF1a?=3D 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 =C2=A0I suggest that in future this poll be extended to indica= te WHY any person indicates they =C2=A0LIKE =C2=A0a functional? As we all k= now, the choice of functional so often depends on what the property of inte= rest is.
>>
>> I suggest initially a relatively short controlled list of properti= es,
>> which can then be extended by =C2=A0=E2=80=9Ccrowd sourcing=E2=80= =9D. Properties =C2=A0I 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. =C2=A0That 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<= br> > 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,
> =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 Dr. V=C3=ADctor Lua= =C3=B1a
>
> --
> =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 \|/
> =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0|^.^|
> +---!OO--\_/--OO!------------------------------+----------------------=
> +-
> ! =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2= =A0Dr.V=C3=ADctor Lua=C3=B1a =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2= =A0 =C2=A0 =C2=A0 !
> ! Departamento de Qu=C3=ADmica F=C3=ADsica y Anal=C3=ADtica =C2=A0 ! > ! Universidad de Oviedo, 33006-Oviedo, Spain =C2=A0 !
> ! e-mail: =C2=A0 victor*fluor.quimica.uniovi.es =C2=A0 =C2=A0 !
> ! phone: +34-9= 85-103491 =C2=A0fax: +34-985-103125 =C2=A0 !
> +----------------------------------------------+
> =C2=A0 GroupPage : http://azufre.quimica.uniovi.es/ =C2=A0(being
> reworked)http://www.ccl.net/cgi-bin/ccl/send_ccl_mess= agehttp://www.ccl
> .net/chemistry/sub_unsub.shtmlhttp://www.ccl.net/spammers.txthttp://www.ccl.net/cgi-bin/ccl/send_ccl_mess= agehttp://www.ccl.net/chemistry/sub_unsub.shtmlhttp://www.ccl.net/spammers.= txt


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--
Steven Bachrach
Semmes Distingui= shed Professor and Assistant VP for Special Projects
Department of Chemistry
Trinity University =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 = =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0Phone: 210-999-7379
1 Trinity Place =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2= =A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0Fax: 210-999-7569
San Antonio, TX 78212 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2= =A0 email: sbach= rach]=[trinity.edu
--047d7b6dc67aad7c3604fae0607d--