From owner-chemistry@ccl.net Fri Jan 25 03:29:00 2013 From: "Ulrike Salzner salzner**gmail.com" To: CCL Subject: CCL:G: weakly bound electrons Message-Id: <-48131-130125032303-31687-nyLsWK86zf6yHin+yjOKHQ() server.ccl.net> X-Original-From: Ulrike Salzner Content-Type: multipart/alternative; boundary=e89a8ff2565674cb3104d418a29e Date: Fri, 25 Jan 2013 10:22:56 +0200 MIME-Version: 1.0 Sent to CCL by: Ulrike Salzner [salzner|-|gmail.com] --e89a8ff2565674cb3104d418a29e Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Dear Pierre, many years ago I investigated the electron affinity of the methyl radical (Chem Phys Lett 1992,199,267). It is exactly such a case as you describe. In short: CCSD(T) is very good. With multireference methods and large basis sets, the electron might simply fly away. One has to be careful with diffuse functions if method does not get the anion bound. The electron will linger in a huge orbital far from the molecule. The best way is to use a reasonably large basis set and then crank up the level until the anion has the lower energy. Only then it makes sense to ask where the electron is. With the methyl anion it turned out that the largest contribution to the binding energy comes from zero point vibration! Regards, Ulrike On Thu, Jan 24, 2013 at 6:04 PM, Pierre Archirel pierre.archirel|-|u-psud.f= r wrote: > > Sent to CCL by: Pierre Archirel [pierre.archirel:-:u-psud.fr] > Dear colleagues, > What is the best method for calculating the small electron affinitiy > (say 0.01 - 0.10 eV) of a rather large system with many equivalent sites. > For my smallest system the valence CAS would require > 37 electrons in 36 orbitals, which is not feasible. > What about MP2, MP4 ? > Is CCSD(T) usable when the electron is not bound at the HF level? > I have gaussian 09 and Molpro available. > Thanks in advance. > > Pierre Archirel > LCP, Universite Paris-Sud, > Orsay, France > pierre.archirel!!u-psud.fr > > > ______________________________**______________________________**__ > > Pierre Archirel > Groupe Th=E9osim: Th=E9orie et Simulation > Laboratoire de Chimie Physique Tel: 01 69 15 63 86 > B=E2t 349 Fax: 01 69 15 61 88 > 91405 Orsay C=E9dex > France pierre.archirel(-)u-psud.fr > ______________________________**______________________________**__ > > > > -=3D This is automatically added to each message by the mailing script = =3D-> http://www.ccl.net/cgi-bin/**ccl/send_ccl_message http://www.ccl.net/cgi-bin/**ccl/send_ccl_message chemistry/announcements/**conferences/ > > Search Messages: http://www.ccl.net/chemistry/**searchccl/index.shtml http://www.ccl.net/spammers.**txt > > RTFI: http://www.ccl.net/chemistry/**aboutccl/instructions/ > > > --=20 Assoc. Prof. Ulrike Salzner Department of Chemistry Bilkent University 06800 Bilkent, Ankara --e89a8ff2565674cb3104d418a29e Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
Dear Pierre,
many years ago I inve= stigated the electron affinity of the methyl radical (Chem Phys Lett 1992,1= 99,267). It is exactly such a case as you describe. In short: CCSD(T) is ve= ry good. With multireference methods and large basis sets, the electron mig= ht simply fly away. One has to be careful with diffuse functions if method = does not get the anion bound. The electron will linger in a huge orbital fa= r from the molecule. The best way is to use a reasonably large basis set an= d then crank up the level until the anion has the lower energy. Only then i= t makes sense to ask where the electron is. With the methyl anion it turned= out that the largest contribution to the binding energy comes from zero po= int vibration!
Regards,
Ulrike


=
On Thu, Jan 24, 2013 at 6:04 PM, Pierre Archirel= pierre.archirel|-|u-psud.fr <owner= -chemistry-.-ccl.net> wrote:

Sent to CCL by: Pierre Archirel [pierre.archirel:-:u-psud.fr]
Dear colleagues,
What is the best method for calculating the small electron affinitiy
(say 0.01 - 0.10 eV) of a rather large system with many equivalent sites. For my smallest system the valence CAS would require
37 electrons in 36 orbitals, which is not feasible.
What about MP2, MP4 ?
Is CCSD(T) usable when the electron is not bound at the HF level?
I have gaussian 09 and Molpro available.
Thanks in advance.

Pierre Archirel
LCP, Universite Paris-Sud,
Orsay, France
pierre.archirel!!u-psud.fr


_____________________________________________________________= _

=A0Pierre Archirel
=A0Groupe Th=E9osim: Th=E9orie et Simulation
=A0Laboratoire de Chimie Physique =A0 =A0 =A0Tel: 01 69 15 63 86
=A0B=E2t 349 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 Fax: 0= 1 69 15 61 88
=A091405 Orsay C=E9dex
=A0France =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 pierre.archirel(-)u-psud.fr
_____________________________________________________________= _



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--
Assoc. Prof. Ulrike Sal= zner
Department of Chemistry
Bilkent University
06800 Bilkent, Ank= ara
--e89a8ff2565674cb3104d418a29e-- From owner-chemistry@ccl.net Fri Jan 25 04:03:00 2013 From: "Eli Lam elizabeth.shlam||gmail.com" To: CCL Subject: CCL: Query on radiative decay rate constant formula Message-Id: <-48132-130125033802-2742-zAdjEACBTo0V+PcSlIc/vw-.-server.ccl.net> X-Original-From: "Eli Lam" Date: Fri, 25 Jan 2013 03:38:01 -0500 Sent to CCL by: "Eli Lam" [elizabeth.shlam _ gmail.com] Dear CCLers, I have been reading papers on radiative decay rate constant. In general, people start of with the formulae: ((16x10^6 pi^3 E^3) /3h(epsilon))* (transition dipole moments), where h is the Planck's constant, epsilon is the vacuum permittivity, and E is the excitation energy, (Inorganic Chemistry, 42, 20, 2003). Yersin starts with the formulae: (64pi^4 E^3 / 3hc^3) *(transition dipole moments), where c is the speed of light (Coordination Chemistry Reviews 255, 2622, 2011). I would like to ask 1) How is the two formula related? 2) How is these two formula derived? Thank you very much! Eli From owner-chemistry@ccl.net Fri Jan 25 05:22:00 2013 From: "Sergio Manzetti sergio.manzetti]_[gmx.com" To: CCL Subject: CCL: Query on radiative decay rate constant formula Message-Id: <-48133-130125051908-7541-wIPDuD3dEUowPwO3FMnNaA!=!server.ccl.net> X-Original-From: "Sergio Manzetti" Content-Type: multipart/alternative; boundary="========GMXBoundary220991359109139981905" Date: Fri, 25 Jan 2013 11:18:59 +0100 MIME-Version: 1.0 Sent to CCL by: "Sergio Manzetti" [sergio.manzetti[-]gmx.com] --========GMXBoundary220991359109139981905 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Hi Elizabeth, It seems their relationship is (2.5x10^5 x c^3) / pi x epsilon This formulation is unknown, at least to me, but it seems this implies a different radial decay, perhaps related to a perturbated condition of some sort. Sergio ----- Original Message ----- > From: Eli Lam elizabeth.shlam||gmail.com Sent: 01/25/13 09:38 AM To: Manzetti, Sergio Subject: CCL: Query on radiative decay rate constant formula Sent to CCL by: "Eli Lam" [elizabeth.shlam _ gmail.com] Dear CCLers, I have been reading papers on radiative decay rate constant. In general, people start of with the formulae: ((16x10^6 pi^3 E^3) /3h(epsilon))* (transition dipole moments), where h is the Planck's constant, epsilon is the vacuum permittivity, and E is the excitation energy, (Inorganic Chemistry, 42, 20, 2003). Yersin starts with the formulae: (64pi^4 E^3 / 3hc^3) *(transition dipole moments), where c is the speed of light (Coordination Chemistry Reviews 255, 2622, 2011). I would like to ask 1) How is the two formula related? 2) How is these two formula derived? Thank you very much! Elihttp://www.ccl.net/cgi-bin/ccl/send_ccl_messagehttp://www.ccl.net/chemistry/sub_unsub.shtmlhttp://www.ccl.net/spammers.txt--========GMXBoundary220991359109139981905 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable Hi Eliza= beth,
=20
=20 It seems their relationship is (2.5x10^5 x c^3) / pi x epsilon
=20
=20
=20 This formulation is unknown, at least to me, but it seems this implies a di= fferent radial decay, perhaps related to a perturbated condition of some so= rt.
=20
=20 Sergio
=20
=20

=20 =C2=A0

=20
=20

=20 ----- = Original Message -----

=20

=20 From: = Eli Lam elizabeth.shlam||gmail.com

=20

=20 Sent: = 01/25/13 09:38 AM

=20

=20 To: Ma= nzetti, Sergio

=20

=20 Subjec= t: CCL: Query on radiative decay rate constant formula

=20
=20
=20
=20 
=20
Sent to CCL by: "Eli  Lam" [elizabeth.shlam _ gmail.com]=20
Dear CCLers,=20

I have been reading papers on radiative decay rate constant.  In general,=
=20
people start of with the formulae: ((16x10^6 pi^3 E^3) /3h(epsilon))*=20
(transition dipole moments), where h is the Planck's constant, epsilon is t=
he=20
vacuum permittivity, and E is the excitation energy, (Inorganic Chemistry, =
42,=20
20, 2003).  Yersin starts with the formulae: (64pi^4 E^3 / 3hc^3) *(transit=
ion=20
dipole moments), where c is the speed of light (Coordination Chemistry Revi=
ews=20
255, 2622, 2011). =20

I would like to ask=20
1) How is the two formula related?=20
2) How is these two formula derived?=20

Thank you very much!=20
Eli=20



-=3D This is automatically added to each message by the mailing script =3D-=
=20=20=20=20=20=20=20=20

Subscribe/Unsubscribe:=20=20=20

Job: http://www.ccl.net/jobs=20=20=20=20=20
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=20
=20
=20

=20 =C2=A0

=20
=20 --========GMXBoundary220991359109139981905-- From owner-chemistry@ccl.net Fri Jan 25 08:18:00 2013 From: "Prof Ponnadurai Ramasami ramchemi++intnet.mu" To: CCL Subject: CCL: Virtual Conference on Computational Chemistry-(1st-31st August 2013)-Call for abstracts Message-Id: <-48134-130125050402-843-IzrrMKdTDfXTv5SN35uc8A^_^server.ccl.net> X-Original-From: "Prof Ponnadurai Ramasami" Content-Language: en-us Content-Type: multipart/alternative; boundary="----=_NextPart_000_000D_01CDFB04.CBA3C100" Date: Fri, 25 Jan 2013 14:03:46 +0400 MIME-Version: 1.0 Sent to CCL by: "Prof Ponnadurai Ramasami" [ramchemi],[intnet.mu] This is a multi-part message in MIME format. ------=_NextPart_000_000D_01CDFB04.CBA3C100 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Dear Sir/Madam, Greetings from Mauritius. A Virtual Conference on Computational Chemistry will be organised by the Computational Chemistry Group of the University of Mauritius. The theme of the conference is "Computational Chemistry in the Digital Age". The Virtual Conference will be held from 1st to 31st August 2013. You are invited to submit an abstract to be considered for the Virtual Conference. The deadline for submission is 1st June 2013. All topics related to Computational Chemistry may be considered. Please visit the website of the Conference and let me know if you need more details. http://sites.uom.ac.mu/vccc/ Looking forward for your participation. Prof Ponnadurai Ramasami Chairman of the Organising Committee How the conference will take place? * There will be a call for abstracts. * Scientific committee will evaluate suitability of each submitted abstract. * For each accepted abstract, author/s will be invited to submit the e-presentation in MS Word, MS Powerpoint, PDF or any other relevant format. Some examples are: (1) PDF format (10 pages) (2) Powerpoint format (10 slides) (3) Video (10 minutes) * E-presentations will be displayed on the website (secured). * Registered participants will be able to download all e-presentations. * Participants can ask questions by sending email/s to the corresponding author for each e-presentation. * When a participant sends an email, the same email is received by all the registered participants. However, it is the responsibility of the corresponding author to reply to the email being asked within 24 hours. When the corresponding author responds by replying the email, the same is received by all the participants. * Full paper (optional) will be reviewed and accepted papers will be collected in the conference proceedings. ------=_NextPart_000_000D_01CDFB04.CBA3C100 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Dear Sir/Madam,

Greetings from Mauritius.

A = Virtual Conference on Computational Chemistry will be organised by the Computational Chemistry Group of the University of Mauritius.

The = theme of the conference is “Computational Chemistry in the Digital = Age”.

The = Virtual Conference will be held from 1st to 31st August = 2013.

You = are invited to submit an abstract to be considered for the Virtual = Conference. The deadline for submission is 1st June = 2013.

All = topics related to Computational Chemistry may be considered.

Please visit the website of the Conference and let me know if you need more = details. 

http://sites.uom.ac.mu/vccc/

Looking forward for your participation.

Prof Ponnadurai Ramasami

Chairman of the Organising Committee

 <= /o:p>

How the conference will take place?

  • There = will be a call for abstracts.
  • Scientific committee will evaluate suitability of each submitted = abstract.
  • For each accepted = abstract, author/s will be invited to submit the e-presentation in MS Word, = MS Powerpoint, PDF or any other relevant format. Some examples = are:
    (1) PDF format (10 pages)
    (2) Powerpoint format (10 slides)
    (3) Video (10 minutes)
  • E-presentations will be displayed on the website (secured).
  • Registered participants will be able to download all = e-presentations.
  • Participants can ask questions by sending email/s to the corresponding author = for each e-presentation.
  • When = a participant sends an email, the same email is received by all the registered participants. However, it is the responsibility of the corresponding author to reply to the email being asked within 24 = hours. When the corresponding author responds by replying the email, the = same is received by all the participants.
  • Full = paper (optional) will be reviewed and accepted papers will be collected = in the conference proceedings.

 

 

 

 

 

------=_NextPart_000_000D_01CDFB04.CBA3C100-- From owner-chemistry@ccl.net Fri Jan 25 21:41:00 2013 From: "John McKelvey jmmckel#gmail.com" To: CCL Subject: CCL: A physical interpretation of RPA Message-Id: <-48135-130125193130-22907-O94Snn+rO+ShSnqXfe7hxQ,server.ccl.net> X-Original-From: John McKelvey Content-Type: text/plain; charset=ISO-8859-1 Date: Fri, 25 Jan 2013 19:31:24 -0500 MIME-Version: 1.0 Sent to CCL by: John McKelvey [jmmckel,,gmail.com] I hate to ask this... My wife is a biochem major and she asked me to give her a definition of "RPA."... I know what the SCF-MO based formulas look like, but tat won't do here... Can someone provide a physical definition of RPA? Regrets, John -- John McKelvey 10819 Middleford Pl Ft Wayne, IN 46818 260-489-2160 jmmckel#,#gmail.com