Subject: Gaussian-92 difficulty... X RAN OUT IN RYSROT

From: [email-masked] (Greg Koyanagi)
Date: Wed, 26 Jan 94 0:49:39 EST

Dear Comp-Chem netters:

I've sent the following letter to Gaussian asking for assistance, however
we do not subscribe to their "On-demand-help-line" so any response I
recieve may not arrive in a timely manner, if at all.

I would appreciate any info or solutions from someone in-the-know or who
has had and conquered a similar problem.

Thanks in advance for any and all help,

Greg Koyanagi                         E-mail ([email-masked])
Department of Chemistry               Voice  519-885-1211 (x6388)
University of Waterloo                FAX    519-746-0453
Waterloo, Ontario, CANADA
N2L 3G1

Text of letter:
************************************************************************
I have been attempting to perform frozen-core MP2 frequency calculations
on small hydrocarbon neutrals and cations and have had difficulty in
persuading the computations to complete.

The computer being used is an SGI with (8x)-33MHz R3000 chips, revision 2.
There are 128 MBytes of main memory and 5GB of scratch disk space.
The version of gaussian gives:
 ***************************************
 Gaussian 92:  SGI-G92RevE.2  4-Aug-1993
              22-Oct-1993
 ***************************************

Several systems have resulted in the computation dying with the error:
=====================================================================
 Use MO integrals over full window.
 2PDM will be sorted in   1 passes.
 Compute integral second derivatives.
 ... and contract with generalized density number  2.
 Use density number 2.
 RysSet:  KIntrp=     2354   KCalc=        0   KAssym=     2821
 Use density number 2.
 Adding in external 2PDM contributions.
 TWLHES:  FMTGEN WAS CALLED     42612 TIMES.
 Compute integral second derivatives.
 DF integral derivatives using scalar Rys method.
 Use density number 2.
 Adding in external 2PDM contributions.
 Standard cutoffs used.
 PQCut1= 1.00D-20 PQCut2= 1.00D-20 PQCut3= 1.00D+02 PQCut4= 1.00D-20
 X RAN OUT IN RYSROT.
 Error termination in Lnk1e.
sh: 9799 Memory fault - core dumped

Which was produced from the input file:
======================================
%Chk=ch2oh02
%NProc=1
%Mem=2800000
#N MP2/6-31+G(2d,2p) GEOM=CHECK GUESS=CHECK FREQ TEST

ch2oh(+) freq

1       1
======================================

The checkpoint file was produced by the following input file:
============================================================
%Chk=ch2oh02
#N MP2/6-31+G(2d,2p) OPT=TIGHT TEST

ch2oh(+)

1 1
C
O C rCO
H1 C rCH1 O HCO1
H2 C rCH2 O HCO2 H1 HCOH
H3 O rOH3 C HOC3 H1 HOCH

rCO 1.252489
rCH1 1.087204
rCH2 1.085003
rOH3 0.981446
HCO1 121.477
HCO2 115.408
HOC3 114.484
HCOH 180.0
HOCH 0.0

============================================================

Which completed and ended with:
====================================================
 Test job not archived.
 1\1\UNIVERSITY OF WATERLOO-WATSCI\FOPT\RMP2-FC\6-31+G(2D,2P)\C1H3O1(1+
 )\KOYANAGI\22-Oct-1993\1\\#N MP2/6-31+G(2D,2P) OPT=TIGHT TEST\\ch2oh(+
 )\\1,1\C\O,1,rCO\H,1,rCH1,2,HCO1\H,1,rCH2,2,HCO2,3,HCOH,0\H,2,rOH3,1,H
 OC3,3,HOCH,0\\rCO=1.252489\rCH1=1.087204\rCH2=1.085003\rOH3=0.981446\H
 CO1=121.477\HCO2=115.408\HOC3=114.484\HCOH=180.\HOCH=0.\\Version=SGI-G
 92RevE.2\State=1-A'\HF=-114.1741398\MP2=-114.5061648\RMSD=2.208e-09\RM
 SF=1.082e-06\Dipole=0.6354071,0.,-0.5293646\PG=CS [SG(C1H3O1)]\\@
====================================================

I have determined that the link executing was calling a utility in
utilnz.F which has the documenting comments:

COPYRIGHTED STUFF DELETED FOR PUBLIC MAILING....
*   
*  Insert here comments for a subroutine that attempts to 
*  determine roots of an equation involved in the 
*  Rys method.  SUBROUTINE RYSROT
*

Subsequently, I have successfully computed the frequencies in the above
instance using freq=numer, however, this would prove too large a task for
some of the systems I wish to study. (My best estimate for the next largest
is 16-20 days and 60-100 days for the system above that).  Similar analytic
computations have completed in 3 to 4 days.

I would appreciate any ideas or information you may have that would allow
me to compute the frequencies using the analytic algorithm.

Sincerly,

Greg Koyanagi                         E-mail ([email-masked])
Department of Chemistry               Voice  519-885-1211 (x6388)
University of Waterloo                FAX    519-746-0453
Waterloo, Ontario, CANADA
N2L 3G1