From owner-chemistry@ccl.net Tue Mar 17 10:19:01 2015 From: "=?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal victor^^^fluor.quimica.uniovi.es" To: CCL Subject: CCL: The importance of analytic second derivatives Message-Id: <-51124-150317101625-12983-9Yf1UKtBkcfhpoSW0/+WYg[A]server.ccl.net> X-Original-From: =?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal Content-disposition: inline Content-transfer-encoding: 8BIT Content-type: text/plain; charset=iso-8859-1 Date: Tue, 17 Mar 2015 15:11:13 +0100 MIME-version: 1.0 Sent to CCL by: =?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal [victor-*-fluor.quimica.uniovi.es] On Mon, Mar 16, 2015 at 05:02:03PM -0400, Brian Skinn bskinn(a)alum.mit.edu wrote: > By 'analytical second derivatives,' do you mean the second derivatives with > respect to nuclear positions? With respect to orbital/etc. coefficients? > Something else? > Brian, 1) Let me elaborate some more your answer to Sergio, as your point is extremely important. 2) No method that I know has implemented the derivatives of the wavefuncion or of the energy with respect to the orbitals, nor with respect to the electronic occupation of orbitals. It would nice to do it. 3) When quantum chemist talk about derivatives we are usually refering to the derivatives of the energy with respect to the nuclear positions. The first derivatives provide the forces that operate in our systems, and the second derivatives provide the curvatures. 4) Lacking analytic expressions for the derivatives of the energy with respect to the nuclear positions you can use numerical aproximations for the derivatives. Let me cite an old article that I published on the use of numerical approximations on this subject J. Chem. Phys. 99 (1993) 7970--7982 doi:10.1063/1.466214 Best regards, Dr. Víctor Luaña -- . . "The hardest part in solving a problem is recognizing / `' \ its existence. Learning the causes CAN be the road to /(o)(o)\ the solution." /`. \/ .'\ -- ¿? / '`'` \ "Lo mediocre es peor que lo bueno, pero también es peor | \'`'`/ | que lo malo, porque la mediocridad no es un grado, es una | |'`'`| | actitud" \/`'`'`'\/ -- Jorge Wasenberg, 2015 ===(((==)))==================================+========================= ! Dr.Víctor Luaña ! Mediocre is worse than ! Departamento de Química Física y Analítica ! good, but it is also ! Universidad de Oviedo, 33006-Oviedo, Spain ! worse than bad, because ! e-mail: victor|*|fluor.quimica.uniovi.es ! mediocrity is not a grade, ! phone: +34-985-103491 fax: +34-985-103125 ! it is an attitude +--------------------------------------------+ GroupPage : http://azufre.quimica.uniovi.es/ (being reworked) From owner-chemistry@ccl.net Tue Mar 17 12:35:00 2015 From: "Abhijit Dutta adutta.chem89**gmail.com" To: CCL Subject: CCL: problems in solving binding energy calculation in DMOL3. Message-Id: <-51125-150317015722-30750-d/3SCY4FZw7ewJJJDPi/3A|-|server.ccl.net> X-Original-From: Abhijit Dutta Content-Type: multipart/alternative; boundary=089e013a214e6ff244051175a3df Date: Mon, 16 Mar 2015 22:57:14 -0700 MIME-Version: 1.0 Sent to CCL by: Abhijit Dutta [adutta.chem89:_:gmail.com] --089e013a214e6ff244051175a3df Content-Type: text/plain; charset=UTF-8 Sir, I am finding difficulties to finding binding energy calculation of 3d metal cluster. how i optimize one single atom . --089e013a214e6ff244051175a3df Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
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=C2=A0I am finding difficulties to finding = binding energy calculation of 3d metal cluster. how i optimize one single a= tom .
--089e013a214e6ff244051175a3df-- From owner-chemistry@ccl.net Tue Mar 17 13:10:00 2015 From: "Sergio Manzetti sergio.manzetti(a)outlook.com" To: CCL Subject: CCL:G: The importance of analytic second derivatives Message-Id: <-51126-150317044418-7831-36ZA2l0SZ7Xx0bUxGlG0Rw**server.ccl.net> X-Original-From: "Sergio Manzetti" Date: Tue, 17 Mar 2015 04:44:16 -0400 Sent to CCL by: "Sergio Manzetti" [sergio.manzetti{}outlook.com] Hi Robert, thanks for this. The approach I prepared to get the full wavefunction of the small system was: 1. QCISD with quadruple excitation. 2. NBO analysis 3. Wavefunction derivation, plus bonding pattern. The reason I use not CC methods is that I get the same message from gaussian as with MP4 or higher order CC methods: "Warning: this job cannot use analytic gradients and so will do many energy evaluations." Thanks! Sergio > From: owner-chemistry~!~ccl.net > To: sergio.manzetti~!~gmx.com > Subject: CCL: The importance of analytic second derivatives > Date: Mon, 16 Mar 2015 19:48:49 -0400 > > > Sent to CCL by: Robert Molt [r.molt.chemical.physics++gmail.com] > Dear Sergio, > > If your goal is to get the best wavefunction possible, why do you need > second derivatives at all? You can get the wavefunction without this. > > Separately, the orbitals you get from a correlated calculation (the > natural orbitals) do not represent the total wavefunction. The total > wavefunction requires many-body effects (more than just any set of > orbitals). > > The natural orbitals from a good wavefunction calculation can give you > the density very accurately, and demonstrate (to varying degrees) which > orbitals are "active" in representing the total wavefunction relative to > the reference determinant. However, they are not the total wavefunction. > > Also, why use QCI methods when you could use coupled cluster methods for > the same cost and improved accuracy? > > On 3/16/15 3:20 PM, Sergio Manzetti sergio.manzetti * outlook.com wrote: > > Sent to CCL by: "Sergio Manzetti" [sergio.manzetti,+,outlook.com] > > Dear Robert. > > > > The question is referring to using ab initio calculations for deriving the exact molecular wavefunction for a small molecule, and report its composition in terms of bonding and antibonding orbitals. The use of natural orbital is critical. The density matrices also. > > > > The point is that the most accurate Methods I have tried (QCISD(TQ)) and others of quadruple excitation do not derive the analytic second derivatives. So I had to choose an ab initio Method that at least converged, and found one. However, this, as the others, does not solve the analytic second derivatives. So for the Scope of the calculation, which role do these derivaties play for revealing the accurate molecular wavefunction? > > > > Thanks! > > > > > > Sent to CCL by: Dr Robert Molt Jr [r.molt.chemical.physics%gmail.com] > > Not sure what is meant by the question, so let me ask some clarifying > > questions. > > > > Are you asking about the importance of analytic vs. finite difference > > second derivatives? > > > > By "exact orbital configurations," are you referring to the natural > > orbitals from a correlated wavefunction calculation getting 1 and 2 > > reduced density matrices? > > > > These are independent questions. > > > > On 03/16/2015 11:05 AM, Sergio Manzetti sergio.manzetti]~[outlook.com wrote: > >> Sent to CCL by: "Sergio Manzetti" [sergio.manzetti~!~outlook.com] > >> Dear all, for ab initio methods which aim to find the exact orbital configuration of small systems, how importance do analytic second derivatives have? What do these operations give to the final result? > >> > >> Thankshttp://www.ccl.net/cgi-bin/ccl/send_ccl_messagehttp://www.ccl.net/chemistry/sub_unsub.shtmlhttp://www.ccl.net/spammers.txt> > > > > -- > Dr. Robert Molt Jr. > r.molt.chemical.physics..gmail.com > Nigel Richards Research Group > Department of Chemistry & Chemical Biology > Indiana University-Purdue University Indianapolis > LD 326 > 402 N. Blackford St. > Indianapolis, IN 46202> > From owner-chemistry@ccl.net Tue Mar 17 13:44:00 2015 From: "Susi Lehtola susi.lehtola:_:alumni.helsinki.fi" To: CCL Subject: CCL: The importance of analytic second derivatives Message-Id: <-51127-150317124051-28721-+7jhMvvcOLgVhlXMWI01kQ|-|server.ccl.net> X-Original-From: Susi Lehtola Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=windows-1252; format=flowed Date: Tue, 17 Mar 2015 09:40:39 -0700 MIME-Version: 1.0 Sent to CCL by: Susi Lehtola [susi.lehtola]|[alumni.helsinki.fi] On 03/17/2015 07:11 AM, Víctor Luaña Cabal victor^^^fluor.quimica.uniovi.es wrote: > 2) No method that I know has implemented the derivatives of the > wavefuncion or of the energy with respect to the orbitals, nor with > respect to the electronic occupation of orbitals. It would nice > to do it. Examples of methods that implement derivatives of the energy with respect to the orbitals are multi-configurational self-consistent field theory, and orbital-optimized theories such as orbital-optimized MP2 and orbital-optimized doubles (OD). -- ----------------------------------------------------------------------- Mr. Susi Lehtola, PhD Chemist Postdoctoral Fellow susi.lehtola]*[alumni.helsinki.fi Lawrence Berkeley National Laboratory http://www.helsinki.fi/~jzlehtol USA ----------------------------------------------------------------------- From owner-chemistry@ccl.net Tue Mar 17 14:34:01 2015 From: "Sergio Manzetti sergio.manzetti::outlook.com" To: CCL Subject: CCL: The importance of analytic second derivatives Message-Id: <-51128-150317143308-22240-08sSVsHL+JMUONGyoeTsAA##server.ccl.net> X-Original-From: "Sergio Manzetti" Date: Tue, 17 Mar 2015 14:33:06 -0400 Sent to CCL by: "Sergio Manzetti" [sergio.manzetti ~ outlook.com] Dear Victor, if the derivatives provide the forces and the curvatures, which aspects of Quantum chemistry are these Critical for? Magnetism? Spin-corrections/spintronics? Thanks Sent to CCL by: =?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal [victor-*-fluor.quimica.uniovi.es] On Mon, Mar 16, 2015 at 05:02:03PM -0400, Brian Skinn bskinn(a)alum.mit.edu wrote: > By 'analytical second derivatives,' do you mean the second derivatives with > respect to nuclear positions? With respect to orbital/etc. coefficients? > Something else? > Brian, 1) Let me elaborate some more your answer to Sergio, as your point is extremely important. 2) No method that I know has implemented the derivatives of the wavefuncion or of the energy with respect to the orbitals, nor with respect to the electronic occupation of orbitals. It would nice to do it. 3) When quantum chemist talk about derivatives we are usually refering to the derivatives of the energy with respect to the nuclear positions. The first derivatives provide the forces that operate in our systems, and the second derivatives provide the curvatures. 4) Lacking analytic expressions for the derivatives of the energy with respect to the nuclear positions you can use numerical aproximations for the derivatives. Let me cite an old article that I published on the use of numerical approximations on this subject J. Chem. Phys. 99 (1993) 7970--7982 doi:10.1063/1.466214 Best regards, Dr. Vctor Luaa -- . . "The hardest part in solving a problem is recognizing / `' \ its existence. Learning the causes CAN be the road to /(o)(o)\ the solution." /`. \/ .'\ -- ? / '`'` \ "Lo mediocre es peor que lo bueno, pero tambin es peor | \'`'`/ | que lo malo, porque la mediocridad no es un grado, es una | |'`'`| | actitud" \/`'`'`'\/ -- Jorge Wasenberg, 2015 ===(((==)))==================================+========================= ! Dr.Vctor Luaa ! Mediocre is worse than ! Departamento de Qumica Fsica y Analtica ! good, but it is also ! Universidad de Oviedo, 33006-Oviedo, Spain ! worse than bad, because ! e-mail: victor^-^fluor.quimica.uniovi.es ! mediocrity is not a grade, ! phone: +34-985-103491 fax: +34-985-103125 ! it is an attitude +--------------------------------------------+ 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 From owner-chemistry@ccl.net Tue Mar 17 15:09:01 2015 From: "=?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal victor]*[fluor.quimica.uniovi.es" To: CCL Subject: CCL: problems in solving binding energy calculation in DMOL3. Message-Id: <-51129-150317143112-20769-8WaBJT6SEMvr4XgcXtrXiA(a)server.ccl.net> X-Original-From: =?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal Content-disposition: inline Content-transfer-encoding: 8BIT Content-type: text/plain; charset=iso-8859-1 Date: Tue, 17 Mar 2015 19:26:40 +0100 MIME-version: 1.0 Sent to CCL by: =?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal [victor ~~ fluor.quimica.uniovi.es] On Mon, Mar 16, 2015 at 10:57:14PM -0700, Abhijit Dutta adutta.chem89**gmail.com wrote: > Sir, > I am finding difficulties to finding binding energy calculation of 3d > metal cluster. how i optimize one single atom . What do you mean by that? What do you want to optimize? guess1: The electronic occupancies of your orbitals? In that case try several occupancies and plot the energies versus the occupancies. guess2: Optimizy the shape of the orbitals? Let me stop here. If you don't explain your purpose nobody can advise you. Regards, Dr. Víctor Luaña -- . . "The hardest part in solving a problem is recognizing / `' \ its existence. Learning the causes CAN be the road to /(o)(o)\ the solution." /`. \/ .'\ -- ¿? / '`'` \ "Lo mediocre es peor que lo bueno, pero también es peor | \'`'`/ | que lo malo, porque la mediocridad no es un grado, es una | |'`'`| | actitud" \/`'`'`'\/ -- Jorge Wasenberg, 2015 ===(((==)))==================================+========================= ! Dr.Víctor Luaña ! Mediocre is worse than ! Departamento de Química Física y Analítica ! good, but it is also ! Universidad de Oviedo, 33006-Oviedo, Spain ! worse than bad, because ! e-mail: victor|*|fluor.quimica.uniovi.es ! mediocrity is not a grade, ! phone: +34-985-103491 fax: +34-985-103125 ! it is an attitude +--------------------------------------------+ GroupPage : http://azufre.quimica.uniovi.es/ (being reworked) From owner-chemistry@ccl.net Tue Mar 17 19:57:01 2015 From: "=?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal victor*o*fluor.quimica.uniovi.es" To: CCL Subject: CCL: The importance of analytic second derivatives Message-Id: <-51130-150317194847-24052-66xJgG2CraHJ45FhYyoAqg!^!server.ccl.net> X-Original-From: =?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal Content-disposition: inline Content-transfer-encoding: 8BIT Content-type: text/plain; charset=iso-8859-1 Date: Wed, 18 Mar 2015 00:44:01 +0100 MIME-version: 1.0 Sent to CCL by: =?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal [victor=fluor.quimica.uniovi.es] On Tue, Mar 17, 2015 at 09:40:39AM -0700, Susi Lehtola susi.lehtola:_:alumni.helsinki.fi wrote: > Examples of methods that implement derivatives of the energy with > respect to the orbitals are multi-configurational self-consistent field > theory, and orbital-optimized theories such as orbital-optimized MP2 and > orbital-optimized doubles (OD). Thanks for the correction. I didn't thought on these before writing. Best regards, Dr. Víctor Luaña -- . . "The hardest part in solving a problem is recognizing / `' \ its existence. Learning the causes CAN be the road to /(o)(o)\ the solution." /`. \/ .'\ -- ¿? / '`'` \ "Lo mediocre es peor que lo bueno, pero también es peor | \'`'`/ | que lo malo, porque la mediocridad no es un grado, es una | |'`'`| | actitud" \/`'`'`'\/ -- Jorge Wasenberg, 2015 ===(((==)))==================================+========================= ! Dr.Víctor Luaña ! Mediocre is worse than ! Departamento de Química Física y Analítica ! good, but it is also ! Universidad de Oviedo, 33006-Oviedo, Spain ! worse than bad, because ! e-mail: victor]=[fluor.quimica.uniovi.es ! mediocrity is not a grade, ! phone: +34-985-103491 fax: +34-985-103125 ! it is an attitude +--------------------------------------------+ GroupPage : http://azufre.quimica.uniovi.es/ (being reworked) From owner-chemistry@ccl.net Tue Mar 17 20:31:00 2015 From: "=?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal victor]|[fluor.quimica.uniovi.es" To: CCL Subject: CCL: The importance of analytic second derivatives Message-Id: <-51131-150317195552-7173-UREJTdP+emxyfK6IDhvQ+w::server.ccl.net> X-Original-From: =?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal Content-disposition: inline Content-transfer-encoding: 8BIT Content-type: text/plain; charset=iso-8859-1 Date: Wed, 18 Mar 2015 00:51:19 +0100 MIME-version: 1.0 Sent to CCL by: =?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal [victor|a|fluor.quimica.uniovi.es] On Tue, Mar 17, 2015 at 02:33:06PM -0400, Sergio Manzetti sergio.manzetti::outlook.com wrote: > > Sent to CCL by: "Sergio Manzetti" [sergio.manzetti ~ outlook.com] > Dear Victor, > > if the derivatives provide the forces and the curvatures, > which aspects of Quantum chemistry are these Critical > for? Magnetism? Spin-corrections/spintronics? Many applications. For instance molecular vibrations; spectroscopy. My experience in the fields you suggest is not very large but maybe. Best regards, Dr. Víctor Luaña -- . . "The hardest part in solving a problem is recognizing / `' \ its existence. Learning the causes CAN be the road to /(o)(o)\ the solution." /`. \/ .'\ -- ¿? / '`'` \ "Lo mediocre es peor que lo bueno, pero también es peor | \'`'`/ | que lo malo, porque la mediocridad no es un grado, es una | |'`'`| | actitud" \/`'`'`'\/ -- Jorge Wasenberg, 2015 ===(((==)))==================================+========================= ! Dr.Víctor Luaña ! Mediocre is worse than ! Departamento de Química Física y Analítica ! good, but it is also ! Universidad de Oviedo, 33006-Oviedo, Spain ! worse than bad, because ! e-mail: victor*o*fluor.quimica.uniovi.es ! mediocrity is not a grade, ! phone: +34-985-103491 fax: +34-985-103125 ! it is an attitude +--------------------------------------------+ GroupPage : http://azufre.quimica.uniovi.es/ (being reworked)