From owner-chemistry@ccl.net Thu Jul 2 01:54:00 2020
From: "E H non ricouhenon*gmail.com" <owner-chemistry|*|server.ccl.net>
To: CCL
Subject: CCL: IGMPlot program
Message-Id: <-54132-200701111232-4965-8NTTzATiSW/akUrf4lgNMA|*|server.ccl.net>
X-Original-From: "E H non" <ricouhenon::gmail.com>
Date: Wed, 1 Jul 2020 11:12:31 -0400
Sent to CCL by: "E H non" [ricouhenon,+,gmail.com]
Dear Colleagues,
We are pleased to announce the new IGMPlot release version 2.6.7 - June 2020,
which is available for download at http://igmplot.univ-reims.fr .
Apologies for any possible cross-posting.
This program identifies and quantifies molecular interactions over a broad
range: from non-covalent to covalent bonding.
IGMPlot relies on an electron-density based descriptor working
with either pro-molecular density or with an electron density obtained
> from wave-function calculations.
New Features:
------------------
- IBSI index: an Intrinsic Bond Strength Index (does not belong to the conventional
class of bond orders like Mulliken or Mayer, or the Delocalization Index)
- BAF index: a Bond Asymmetry Factor
- WFX file format is now supported
- Development of a scoring function from pro-molecular electron density
(possibility to probe non-covalent inter-fragment interactions or weak intra-molecular interactions)
- Quantifying intra-molecular pi-pi stacking at the QM level of theory
- Accelerated performances
Kind regards.
Eric Hnon
Prof. Eric Henon
ICMR (Institut de Chimie Molculaire de Reims)
Groupe Biomolecules : Synthese et Mecanismes d'Action
UMR CNRS 7312
Universit de Reims Champagne-Ardenne
51687 Reims Cedex 2 BP 39
FRANCE
eric.henon/./univ-reims.fr
From owner-chemistry@ccl.net Thu Jul 2 11:13:00 2020
From: "Muhammed Buyuktemiz mbtemiz3]~[gmail.com" <owner-chemistry^server.ccl.net>
To: CCL
Subject: CCL: Reaction of an anion with a closed shell molecule with CASSCF
Message-Id: <-54133-200702041914-4643-8X2Ue23Q22cm3IgdFUssxg^server.ccl.net>
X-Original-From: "Muhammed Buyuktemiz" <mbtemiz3++gmail.com>
Date: Thu, 2 Jul 2020 04:19:10 -0400
Sent to CCL by: "Muhammed Buyuktemiz" [mbtemiz3^gmail.com]
Dear CCLers,
I am trying to investigate the electron transfer processes for a reaction
between an anion and a closed shell molecule. As a specific example, you
may consider the reaction between hydroxide and acyl chloride.
Initially, I am placing two species at 10 A apart from each other and
presume that the two are infinitely separated, i.e the ion and the acyl
chloride don't `feel` each other. Later on I am carrying relaxed geometry
optimizations by keeping inter-molecular distance r constant while r is
decreased in subsequent calculations.
However, I am having difficulty in understanding/interpreting the
wavefunction for the infinitely separated species. At 10 A, CASSCF
optimized wavefunction* shows two major configurations each with 0.60
coefficients. The first configuration shows what I would normally expect,
an OH(-) ion and a closed shell Acyl Chloride electronic structure. The
problem I have is related to the second configuration; This configuration
shows that an electron transfer takes place at 10 A and the electron is
located on one of the antibonding orbitals of the acyl chloride, yielding
OH(0) + Acyl Chloride(-) type of electronic structure.
I assume this is not chemically correct (since the two are infinitely
separated) and doesn't allow me to investigate the perturbations induced
when OH- approaches to Acyl Chloride**. But most importantly, since Acyl
Chloride now has an extra electron located on the antibonding orbital, C-
Cl bond breaks up in the geometry optimization calculations.***
My initial thought on the problem was that this might be an unbalanced
active space issue but various combinations also led to the same outcome.
I now realize this may not surprising due to the variational nature of
the calculation; OH(0) + Acyl Chloride(-) configuration is as
important/stable as the OH(-) + Acyl Chloride configuration. However this
sentiment alone does not fix the issue and I am stuck.
Is there any way to work around this issue that will allow me to
investigate what `happens` to orbitals on the OH- approach?
Any suggestions are greatly appreciated. Thank you
*: rest of the coefficients are smaller than 0.1.
**: this problem also persists for smaller/larger intermolecular
distances and choosing an arbitrary 10 A is not a problem.
***: OH(-) -- Acyl Chloride distance is kept at 10 A.
From owner-chemistry@ccl.net Thu Jul 2 15:19:01 2020
From: "Alan Shusterman alan(_)reed.edu" <owner-chemistry++server.ccl.net>
To: CCL
Subject: CCL: Reaction of an anion with a closed shell molecule with CASSCF
Message-Id: <-54134-200702143441-6283-bDNXHchLbTzCaChYSw15RA++server.ccl.net>
X-Original-From: Alan Shusterman <alan%%reed.edu>
Content-Type: multipart/alternative; boundary="000000000000e8895205a979a8c2"
Date: Thu, 2 Jul 2020 11:34:22 -0700
MIME-Version: 1.0
Sent to CCL by: Alan Shusterman [alan..reed.edu]
--000000000000e8895205a979a8c2
Content-Type: text/plain; charset="UTF-8"
Dear Muhammed,
Unfortunately, I can't shed any light on the technical aspects of the
CASSCF calculation, but *qualitatively*, what you describe looks very much
like the "curve crossing model" of chemical reactivity that has been used
by Shaik and Pross and others. If you are looking for qualitative insights,
I would search "curve crossing model". Good luck with your calculations.
Alan
On Thu, Jul 2, 2020 at 10:01 AM Muhammed Buyuktemiz mbtemiz3]~[gmail.com <
owner-chemistry###ccl.net> wrote:
>
> Sent to CCL by: "Muhammed Buyuktemiz" [mbtemiz3^gmail.com]
> Dear CCLers,
>
> I am trying to investigate the electron transfer processes for a reaction
> between an anion and a closed shell molecule. As a specific example, you
> may consider the reaction between hydroxide and acyl chloride.
>
> Initially, I am placing two species at 10 A apart from each other and
> presume that the two are infinitely separated, i.e the ion and the acyl
> chloride don't `feel` each other. Later on I am carrying relaxed geometry
> optimizations by keeping inter-molecular distance r constant while r is
> decreased in subsequent calculations.
> However, I am having difficulty in understanding/interpreting the
> wavefunction for the infinitely separated species. At 10 A, CASSCF
> optimized wavefunction* shows two major configurations each with 0.60
> coefficients. The first configuration shows what I would normally expect,
> an OH(-) ion and a closed shell Acyl Chloride electronic structure. The
> problem I have is related to the second configuration; This configuration
> shows that an electron transfer takes place at 10 A and the electron is
> located on one of the antibonding orbitals of the acyl chloride, yielding
> OH(0) + Acyl Chloride(-) type of electronic structure.
>
> I assume this is not chemically correct (since the two are infinitely
> separated) and doesn't allow me to investigate the perturbations induced
> when OH- approaches to Acyl Chloride**. But most importantly, since Acyl
> Chloride now has an extra electron located on the antibonding orbital, C-
> Cl bond breaks up in the geometry optimization calculations.***
>
> My initial thought on the problem was that this might be an unbalanced
> active space issue but various combinations also led to the same outcome.
> I now realize this may not surprising due to the variational nature of
> the calculation; OH(0) + Acyl Chloride(-) configuration is as
> important/stable as the OH(-) + Acyl Chloride configuration. However this
> sentiment alone does not fix the issue and I am stuck.
>
> Is there any way to work around this issue that will allow me to
> investigate what `happens` to orbitals on the OH- approach?
>
> Any suggestions are greatly appreciated. Thank you
>
>
> *: rest of the coefficients are smaller than 0.1.
> **: this problem also persists for smaller/larger intermolecular
> distances and choosing an arbitrary 10 A is not a problem.
> ***: OH(-) -- Acyl Chloride distance is kept at 10 A.>
>
>
--
Alan Shusterman
Chemistry Department
Reed College
3203 SE Woodstock Blvd
Portland, OR 97202-8199
503-517-7699
http://blogs.reed.edu/alan/
"Patience, persistence, and a sense of humor." Dave Barrett (1956-2017,
Reed College '77)
--000000000000e8895205a979a8c2
Content-Type: text/html; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
<div dir=3D"ltr"><div>Dear Muhammed,</div><div><br></div><div>Unfortunately=
, I can't shed any light on the technical aspects of the CASSCF calcula=
tion, but <u>qualitatively</u>, what you describe looks very much like the =
"curve crossing model" of chemical reactivity that has been used =
by Shaik and Pross and others. If you are looking for qualitative insights,=
I would search "curve crossing model". Good luck with your calcu=
lations.</div><div><br></div><div>Alan<br></div></div><br><div class=3D"gma=
il_quote"><div dir=3D"ltr" class=3D"gmail_attr">On Thu, Jul 2, 2020 at 10:0=
1 AM Muhammed Buyuktemiz mbtemiz3]~[<a href=3D"http://gmail.com">gmail.com<=
/a> <<a href=3D"mailto:owner-chemistry###ccl.net">owner-chemistry###ccl.net<=
/a>> wrote:<br></div><blockquote class=3D"gmail_quote" style=3D"margin:0=
px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><=
br>
Sent to CCL by: "Muhammed=C2=A0 Buyuktemiz" [mbtemiz3^<a href=3D"=
http://gmail.com" rel=3D"noreferrer" target=3D"_blank">gmail.com</a>]<br>
Dear CCLers,<br>
<br>
I am trying to investigate the electron transfer processes for a reaction <=
br>
between an anion and a closed shell molecule. As a specific example, you <b=
r>
may consider the reaction between hydroxide and acyl chloride. <br>
<br>
Initially, I am placing two species at 10 A apart from each other and <br>
presume that the two are infinitely separated, i.e the ion and the acyl <br=
>
chloride don't `feel` each other. Later on I am carrying relaxed geomet=
ry <br>
optimizations by keeping inter-molecular distance r constant while r is <br=
>
decreased in subsequent calculations. <br>
However, I am having difficulty in understanding/interpreting the <br>
wavefunction for the infinitely separated species. At 10 A, CASSCF <br>
optimized wavefunction* shows two major configurations each with 0.60 <br>
coefficients. The first configuration shows what I would normally expect, <=
br>
an OH(-) ion and a closed shell Acyl Chloride electronic structure. The <br=
>
problem I have is related to the second configuration; This configuration <=
br>
shows that an electron transfer takes place at 10 A and the electron is <br=
>
located on one of the antibonding orbitals of the acyl chloride, yielding <=
br>
OH(0) + Acyl Chloride(-) type of electronic structure. <br>
<br>
I assume this is not chemically correct (since the two are infinitely <br>
separated) and doesn't allow me to investigate the perturbations induce=
d <br>
when OH- approaches to Acyl Chloride**. But most importantly, since Acyl <b=
r>
Chloride now has an extra electron located on the antibonding orbital, C-<b=
r>
Cl bond breaks up in the geometry optimization calculations.*** <br>
<br>
My initial thought on the problem was that this might be an unbalanced <br>
active space issue but various combinations also led to the same outcome. <=
br>
I now realize this may not surprising due to the variational nature of <br>
the calculation; OH(0) + Acyl Chloride(-) configuration is as <br>
important/stable as the OH(-) + Acyl Chloride configuration. However this <=
br>
sentiment alone does not fix the issue and I am stuck.<br>
<br>
Is there any way to work around this issue that will allow me to <br>
investigate what `happens` to orbitals on the OH- approach?<br>
<br>
Any suggestions are greatly appreciated. Thank you<br>
<br>
<br>
*: rest of the coefficients are smaller than 0.1.<br>
**: this problem also persists for smaller/larger intermolecular <br>
distances and choosing an arbitrary 10 A is not a problem.<br>
***: OH(-) -- Acyl Chloride distance is kept at 10 A.<br>
<br>
<br>
<br>
-=3D This is automatically added to each message by the mailing script =3D-=
<br<br=<br<br>
<br>
E-mail to subscribers: <a href=3D"mailto:CHEMISTRY###ccl.net" target=3D"_blan=
k">CHEMISTRY###ccl.net</a> or use:<br>
=C2=A0 =C2=A0 =C2=A0 <a href=3D"http://www.ccl.net/cgi-bin/ccl/send_ccl_mes=
sage" rel=3D"noreferrer" target=3D"_blank">http://www.ccl.net/cgi-bin/ccl/s=
end_ccl_message</a><br>
<br>
E-mail to administrators: <a href=3D"mailto:CHEMISTRY-REQUEST###ccl.net" targ=
et=3D"_blank">CHEMISTRY-REQUEST###ccl.net</a> or use<br>
=C2=A0 =C2=A0 =C2=A0 <a href=3D"http://www.ccl.net/cgi-bin/ccl/send_ccl_mes=
sage" rel=3D"noreferrer" target=3D"_blank">http://www.ccl.net/cgi-bin/ccl/s=
end_ccl_message</a><br>
<br<br>
=C2=A0 =C2=A0 =C2=A0 <a href=3D"http://www.ccl.net/chemistry/sub_unsub.shtm=
l" rel=3D"noreferrer" target=3D"_blank">http://www.ccl.net/chemistry/sub_un=
sub.shtml</a><br>
<br>
Before posting, check wait time at: <a href=3D"http://www.ccl.net" rel=3D"n=
oreferrer" target=3D"_blank">http://www.ccl.net</a><br>
<br>
Job: <a href=3D"http://www.ccl.net/jobs" rel=3D"noreferrer" target=3D"_blan=
k">http://www.ccl.net/jobs</a> <br>
Conferences: <a href=3D"http://server.ccl.net/chemistry/announcements/confe=
rences/" rel=3D"noreferrer" target=3D"_blank">http://server.ccl.net/chemist=
ry/announcements/conferences/</a><br>
<br>
Search Messages: <a href=3D"http://www.ccl.net/chemistry/searchccl/index.sh=
tml" rel=3D"noreferrer" target=3D"_blank">http://www.ccl.net/chemistry/sear=
chccl/index.shtml</a><br>
<br<br>
=C2=A0 =C2=A0 =C2=A0 <a href=3D"http://www.ccl.net/spammers.txt" rel=3D"nor=
eferrer" target=3D"_blank">http://www.ccl.net/spammers.txt</a><br>
<br>
RTFI: <a href=3D"http://www.ccl.net/chemistry/aboutccl/instructions/" rel=
=3D"noreferrer" target=3D"_blank">http://www.ccl.net/chemistry/aboutccl/ins=
tructions/</a><br>
<br>
<br>
</blockquote></div><br clear=3D"all"><br>-- <br><div dir=3D"ltr" class=3D"g=
mail_signature"><div dir=3D"ltr"><div><div dir=3D"ltr"><div><div dir=3D"ltr=
">Alan Shusterman<br>Chemistry Department<br>Reed College<br>3203 SE Woodst=
ock Blvd<br>Portland, OR 97202-8199<br>503-517-7699<br><a href=3D"http://bl=
ogs.reed.edu/alan/" target=3D"_blank">http://blogs.reed.edu/alan/</a><br>&q=
uot;Patience, persistence, and a sense of humor." Dave Barrett (1956-2=
017, Reed College '77)<br></div></div></div></div></div></div>
--000000000000e8895205a979a8c2--