Subject: Summary of MOPAC7 on a PC

From: David Close <[email-masked]>
Date: Tue, 06 Dec 1994 20:21:23 -0500 (EST)

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 I sent the following message to CCL on Nov. 29, 1994, seeking help
 in using MOPAC on a Pentium.  I have received a number of useful
 suggestions which are summarized below.  Thanks to all.
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 Original Message:
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Date: Tue, 29 Nov 1994 14:38:11 -0500 (EST)
From: David Close <[email-masked]>
Subject: CCL:MOPAC on PC's
To: [email-masked]
Organization: East Tennessee State University
 
  Dear Netters:
  I would like to know if others have had success with MOPAC or AMPAC
on a PC.  I am trying to use Ivar Koppel's MOPAC 7.1 on my Gateway
Pentium (P5-66).  Ivar sent me the FORTRAN code which I compiled using
Microsoft's Powerstation 32-bit compiler.  The program executes, but
gives results that differ from some of the popular tests examples.
  I need to know if others have had similar problems.  Some users have
mentioned the use of compilers from Microway or Lahey.  I am wondering
if this is important.  Also it would help to know if Ivar's program has
given reliable results in other situations.  Then there is this Pentium
division error that everyone is discussing.  Can this influence MO
calculations?
  Regards,  Dave Close.
 
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Reply from Ken Fountain about using the Lahey compiler.
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Date:        Tue, 29 Nov 94 15:01:33 CST
From:        "FOUNTAIN, KEN" <[email-masked]>
To:          <[email-masked]>
Subject: Re: CCL:MOPAC on PC's
In-Reply-To: In reply to your message of TUE 29 NOV 1994 03:38:11 CST
 
I think it can.  If you send me the code for MOPAC7.1 I can compile it
with a Lahey compiler with a DX@66mHz chip and we can compare results.
Ken Fountain
Northeast Missouri State University
Science Hall
Kirksville, MO 63501
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Reply from Janusz Mrozek warning about MICROSOFTS POWERSTATION FTN
compiler.
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Return-Path: <[email-masked]>
From: <[email-masked]>
Organization:  Faculty of Chemistry, UJ
To: David Close <[email-masked]>
Date:          Wed, 30 Nov 1994 08:22:23 MET+2
Subject:       Re: CCL:MOPAC on PC's
Dear Dr. Close,
    Compiler is the thing that makes a real difference when moving
>from mainframe codes to the PC. In my opinion Microsoft should be
legally forbidden to touch Fortran compilers. We are running for more
than two years an OS/2 version of MOPAC 6.0 on our PC machines, and
it reproduces the results from other machines to the very last digit,
provided such a thing as reproducible AMPAC/MOPAC results do exist.
We are using MICROWAY FTN compiler (an older version) and I think
this is one of the best compilers I ever worked with. If you are
interested in a running MOPAC 6.0 code you can ftp it as an anonymous
user from:  Trurl.ch.uj.edu.pl, directory is mopac6/os2. The MOPAC 7
code should be there in about the beginning of the year.
Best regards,
Janusz Mrozek
====================================================
Janusz Mrozek,
Department of Theoretical Chemistry
& Department of Computational Methods in Chemistry
Faculty of Chemistry,
Jagiellonian University
3 R. Ingardena St.
30-060 Cracow, Poland
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Reply from Ivar Koppel about various compliers used on MOPAC7
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 30 Nov 1994 11:20:43 UTC+0100
Date: Wed, 30 Nov 1994 11:20:43 UTC+0100
From: Ivar Koppel <[email-masked]>
Subject: mopac
That should be a lot of time ago when I posted you that Mopac..
Can you remember me some details? I think you got the sources from
tera.chem.ut.ee. Some months ago somebody posted note on CCL that
mopac 7 contains some bugs, and I fixed those, but at the very
beginning there were unmodified sources at tera. What compiler
are you using? I have compiled the code on both using MS Powerstation
Fortran 1.0 and f2c+gcc combination, the results differ a bit. (sometimes
Powerstation version did 1 more iteration cycle (on large molecule) than
the gcc compiled version, but differencis on final heat of formation
were less than 0.000xx Kcal/mol. Right now I m using the same sources
on Linux, gcc+f2c , and results are fine. The only problem detected
so far that in eigenvector following calculation the calculation aborts
sometimes, giving message "CONSULT PROGRAMMER, etc". But I haven't
noticed incorrect results. At present time I'm working in Madrid,
so perhaps you can use my E-mail address here to send some more
details. For verification you can use mopac6 from www.ccl.net,
directory should be /pub/chemistry/software/dos/mopac_for_dos or something
I haven't got any complaints for that program. The sources for mopac7 are
also available at solaris.ims.ac.jp , but I think they are unmodified.
To compile them under dos you must comment the DATE and TIME calls, I
think in SECOND.F
 
 Best regards,
 Ivar
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 Reply from Klaus-Peter Gulden.  Note:  I have had problems contacting
 him.  All my messages at the address given have come bouncing back.
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Return-Path: <[email-masked]>
Date: Wed, 30 Nov 1994 16:19:27 +0100 (MET)
From: Klaus-Peter Gulden <gulden@wocx03>
Subject: Re: CCL:MOPAC on PC's
 
I've ported MOPAC6.0 on Linux! I don't know whether this seems to be an
appropriate solution for you. All test files have been successfully
calulated. It's compiled with the f2c converter and subsequent gcc
compilation. Only minor changes were neccessary to make the program
run on a LinuX-platform.
You don't mention your operating system, but if you are interested I would
like to give either the sources or the executables.

> mentioned the use of compilers from Microway or Leahey.  I am wondering
> if this is important.  Also it would help to know if Ivar's program has
> given reliable results in other situations.  Then there is this Pentium
> division error that everyone is discussing.  Can this influence MO
> calculations?
 
Are the sources to MOPAC7.1 free to the public? In this case you can give
the FORTRAN-files and I try to port it on LinuX. So after that we can see
whether the numerical problems are due to the PENTIUM-division bug or
due to the Microsoft SUPER POWER HYPER ..... (and so on) Compiler (or
what do the comercials say?).

ok, see you and bye
Klaus-Peter

 ------------------------------------------------------------------------
| Klaus-Peter Gulden | Institut fuer Org. Chemie, Universitaet Wuerzburg |
| Am Hubland         | mail  :  [email-masked]           |
| D-97074 Wuerzburg  | voice :  (0049)-(0)-931-888-4750                  |
| Germany            | fax   :  (0049)-(0)-931-888-4750                  |
 ------------------------------------------------------------------------
 
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Reply from S. Shapiro reporting similar problems with MOPAC 6.
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Return-Path: <[email-masked]>
Date: Wed, 30 Nov 1994 16:32:25 +0100 (MET)
From: "Hr Dr. S. Shapiro" <[email-masked]>
Sender: [email-masked]
Subject: MOPAC 7 for PC
 
Dear Prof. Dr. Close;
 
     Thank you for replying so promptly to my request for contact.
 
     I have been using a PC version of MOPAC 6.0, and wished to "upgrade" to
MOPAC 7.  I obtained the FORTRAN files from Prof. Dr. Koppel, but was unable
to compile it into a PC-executable form.  I then sent it to colleagues in
Belgium and Israel, and apparently they haven't been able to compile it,
either.  The issue rested at that stage until I saw your posting in CCL.
Under these circumstances, I should be very grateful if you would send me
a unencoded zipped version of your working version of MOPAC 7 compiled for
execution on a PC fitted with MS-DOS 6.22.  If you wish, I can send you a
copy of my version of MOPAC 6.0, which I _know_ works properly, and then
we can compare notes  Please note that my server will store very large
files  for me until I elect to download them.
 
   By the eay, have you ever made a stab at trying to compile the latest
version of MOPAC, viz. MOPAC93, on a DOS machine?  Do you know just what
 are the differences between the capabilities of MOPAC 6.0, MOPAC 7, and
 MOPAC93? I would also be very interested in learning of other responses
that you may receive to your CCL posting.

 Thank you for your time.  I look forward to hearing from you in the near
future.

Your sincerely,
 
(Dr.) S. Shapiro
Institut fuer orale Mikrobiologie und allgemeine Immunologie
Zentrum fuer Zahn-, Mund-, und Kieferheilkunde der Universitaet Zuerich
Plattenstrasse 11
Postfach
CH-8028 Zuerich, Switzerland
 
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Most helpful reply from Rainer Koch offering to help check some of
my poor results.
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From: Rainer Koch <[email-masked]>
Message-Id: <[email-masked]>
Subject: Re: CCL:MOPAC on PC's
To: [email-masked] (David Close)
Date: Thu, 1 Dec 94 8:32:48 MEZ
 
Would you be so kind to send me some of your faulty results? I have done a
port of MOPAC 93 to PC`s some time ago using Powerstation. It would be
therefore interesting to see whether it is a problem of a) MOPAC 7 (Ivar`s
or  the original code) b) Pentium FDIV c) FORTRAN Powerstation.
 
        Rainer Koch
 
******************************************************************************
*       Rainer Koch                                                          *
*       Institut fuer Organische und Makromolekulare Chemie                  *
*       Universitaet Jena                                                    *
*       Humboldtstr. 10                                                      *
*       07743 Jena                                                           *
*       Germany                                                              *
*                                                                            *
*       E-mail: [email-masked]                                           *
*       E-mail: [email-masked]                                 *
*       Fax:    0049/0-3641-6-35600                                          *
******************************************************************************
From: Rainer Koch <[email-masked]>
Message-Id: <[email-masked]>
Subject: MOPAC x/PC
To: [email-masked] (David Close)
Date: Fri, 2 Dec 94 9:55:08 MEZ
Dear Dave,
 
Anyway, if you are interested in source code and/or executables for a variety
of compilers, just ask us :-) we (my collegue Bernd Wiedel and myself)
have ported MOPAC 6 to PC`s back in 1991 using Mircoway Fortran and a Phar Lap
DOS-Extender (published at QCPE as QCMP 113). Other versions for Microsoft
Powerstation (Fortran) and the gcc compiler exist as well as versions of
MOPAC 7 and MOPAC 93. With these programs you can run MOPAC in a DOS box
under Windows even in the background. There is no need to change to Linux
unless you want to.
 
Hope this will be of some help.
 
                Best regards, Rainer.
 
**************************************************************************
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NOTE:  I have had several more exchanges with Rainer (exchanging test
outputs.  Rainer is convinced that the problems I am having are mot
very significant, and that indeed my version of MOPAC 7 is ok.  He
has suggested a number of things to try (which I will do as soon as
possible.
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More from Ivar Koppel after I wrote him.
========================================================================
 
Return-Path: <[email-masked]>
 
I used mopac 7.1 with powerstation for calculating heats of formation,
and the results are the same that of mopac 6 on convex or VAX. Maybe
on case when molecule converges badly the mopac 7 was better.
f2c+gcc means using fortran to C translator and GNU C compiler from
Open Software Foundation. Linux is a free Unix clone, it has now
Watcom fortran but I have used the free fortran to C and gnu C
combination, the penalty is told to be 10% perfomance increase.
BTW, I have never carried out reaction path calculations using mopac 7 so
I dont know how it works. The "porting" of mopac 7 to DOS means that
I commented some lines in SECOND.F and somewhere where the DATE call is made,
otherwise its the standard code for sun. I got it from solaris.ims.ak.jp,
and as I found out that only a few people know that mopac 7 is freely
available I compiled it and said that such thing is available. By the
way, J.Stewart is always offically saing that mopac 93 is the right thing
for production work :-). Ok, enough of jokes, I m myself very much interested
in finding out what is the problem with mopac 7.
 
Best regards,
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Reply from Wally Reiher expressing similar problems getting MOPAC to
work on a PC.
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From: [email-masked] (Walter E. Reiher III)
Message-Id: <[email-masked]>
Subject: Re: CCL:MOPAC on PC's
To: [email-masked] (David Close)
Date: Fri, 2 Dec 1994 12:21:02 -0800 (PST)
David,

I have been struggling to port MOPAC93 to Windows NT and DOS (with a DOS
extender, of course) using the Watcom compiler and having absolutely no
luck.  I have gone through all kinds of contortions trying to figure out
why the program returns results which differ substantially from the
results I obtained with the same code on an SGI.  In some cases,
minimizations which converge on the SGI don't on the Pentium.
     I have also been struggling with Watcom techincal support on this
one and am not pleased with their response so far, but I haven't yet
given up on them.
     After this experience, I was considering purchasing MS FORTRAN
PowerStation, but after reading your post, I'm not so sure.  At least
the PowerStation demo compiler I got compiled the program on the first
try, which is more than I could do with the Watcom compiler--I just
can't figure out how to link it with the Microsoft linker.  Do you have
a linker script you can share with me?
 
I am very interested in hearing your experiences with this--I'd
appreciate seeing your summary of responses.  I'd be happy to share more
details with you if I can be of any help.
 
Wally
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Walter E. Reiher III, Ph.D.                            [email-masked]
Consultant in Computational Chemistry
P.O. Box 61056                                        voice 408-720-0240
Sunnyvale, CA 94088                                     fax 408-720-0378
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SUMMARY:
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  That's the summary so far.  I obviously have a lot of follow up work
to do.  Some have suggested switching to OS/2.  OS/2 WARP is available
for ca. $75. but must be used with Windows NT.  After New Year there
is supposed to be a complete operating system from IBM that doesn't
depend on Windows.
  Others have suggested MICROWAY's FTN compiler.  They cost $695. for
the 486 version and $995. for the Pentium version.  That's a lot of
money to spend for something the may or may represent an improvement.
  Several people suggested LINUX, but Rainer Koch says this is not
necessary.
  In reading the above messages it appears that other are having pro-
blems with getting MOPAC to work on a PC.  I am going to continue
testing the version I have, and they I will summarize the results.
 
Thanks again.
David Close
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