<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META http-equiv=Content-Type content="text/html; charset=koi8-r">
<META content="MSHTML 6.00.2800.1491" name=GENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY bgColor=#ffffff>
<DIV><FONT face=Arial size=2>Dear All, </FONT></DIV>
<DIV><FONT face=Arial size=2>We have encountered a memory problem during of
CASPT2(23,15) calculation of C2H3O2 species. We are using a dual
Itanum 2 1.5GHz workstation with 8Gb of memory and 8 Gb of
swap space.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Input looks like</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>***,C2H3O2 TS
9<BR>memory,1000,m;<BR>file,2,c2h3o2_9.wfu;<BR>geometry={angstrom;<BR> c,
0 ,-0.01897, -0.0666 ,
0.4391<BR> c,
0 , -1.36099, -0.18654,
-0.11713<BR> h,
0 , 0.05533, -0.03293,
1.51564<BR> h,
0 , -2.2241 , 0.09429,
0.42556<BR> h,
0 , -1.45278, -0.35638,
-1.17026<BR> o,
0, 0.50073, 1.0631 ,
-0.21201<BR> o,
0, 0.97344, -0.84162,
-0.16122}<BR>basis=vtz<BR>int<BR>!rhf;occ,16;closed,15;wf,31,1,1;<BR>!mcscf;occ,19;closed,4;wf,31,1,1;orbprint,10;<BR>rs2;occ,19;closed,4;core,4;wf,31,1,1;<BR></FONT><FONT
face=Arial size=2></FONT></DIV>
<DIV><FONT face=Arial size=2>In the end I have the following
output:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>1PROGRAM * RS2 (Multireference RS Perturbation
Theory) Authors: H.-J. Werner<BR> (1993), P. Celani
(1998)</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV><FONT face=Arial size=2>
<DIV><BR> Convergence thresholds: THRVAR = 1.00D-08 THRDEN =
1.00D-06</DIV>
<DIV> </DIV>
<DIV> Number of optimized states: 1 Roots:
1<BR> Number of reference states: 1 Roots: 1</DIV>
<DIV> </DIV>
<DIV> Reference
symmetry:
1 Doublet<BR> Maximum shell inside
CICON 7</DIV>
<DIV> </DIV>
<DIV> Maximum number of shells reduced from 7 to
6<BR> Maximum number of spin couplings: 132</DIV>
<DIV> </DIV>
<DIV> Reference space: 71955 conf 305760
CSFs<BR> N elec internal: 71955 conf 305760
CSFs<BR> N-1 el internal: 157950 conf 1337700
CSFs<BR> N-2 el internal: 306735 conf 5245240
CSFs</FONT></DIV>
<DIV><FONT face=Arial size=2>Number of electrons in valence
space:
23<BR> Maximum number of open shell orbitals in reference space:
7<BR> Maximum number of open shell orbitals in internal spaces:
11</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV><FONT face=Arial size=2>
<DIV><BR> Number of core
orbitals: 4
( 4 )<BR> Number of active
orbitals: 15 ( 15 )<BR> Number of
external orbitals: 143 ( 143 )</DIV>
<DIV> </DIV>
<DIV> Molecular orbitals read from record
2140.2 Type=MCSCF/NATURAL (state 1.1)</DIV>
<DIV> </DIV>
<DIV> Integral transformation finished. Total CPU: 16.20 sec,
npass= 1 Memory used<BR>: 5.77 MW</DIV>
<DIV> </DIV>
<DIV> Number of p-space configurations: 49</DIV>
<DIV> </DIV>
<DIV> Reference wavefunction optimized for reference space (refopt=1)</DIV>
<DIV> </DIV>
<DIV> State Reference Energy<BR>
1 -227.20596745</DIV>
<DIV> Number of blocks in overlap matrix:
2 Smallest eigenvalue: 0.11D-01<BR> Number of N-2
electron functions: 225<BR> Number of N-1 electron
functions: 1337700</DIV>
<DIV> </DIV>
<DIV> Number of internal
configurations:
305760<BR> Number of singly external
configurations: 191291100<BR> Number of doubly
external configurations:
2301585<BR> Total number of contracted configurations:
193898445<BR> Total number of uncontracted configurations:53707038840</DIV>
<DIV> </DIV>
<DIV> Weight factors for SA-density in H0: 1.000000</DIV>
<DIV> </DIV>
<DIV> FIMAX= 0.29D+00 FXMAX= 0.11D-04 DIAG=
F F NOREF=1 NOINT=0 IHPPD=2</DIV>
<DIV> </DIV>
<DIV> Nuclear
energy:
112.31304506<BR> Core
energy:
-233.39134100<BR> Zeroth-order valence
energy: -17.12532307</DIV>
<DIV> Zeroth-order total
energy:
-138.20361901<BR> First-order
energy:
-89.00234844</DIV>
<DIV> </DIV>
<DIV> There are only all-active singles.<BR> Contracted Singles code
is turned off.</DIV>
<DIV> </DIV>
<DIV><BR> Using uncontracted singles</DIV>
<DIV> </DIV>
<DIV> noint is 2</DIV>
<DIV> </DIV>
<DIV> Diagonal Coupling coefficients
finished.
Storage: 1477293 words,<BR>CPU-Time: 1.48
seconds.<BR> Energy denominators for pairs finished in 0
passes. Storage: 1411722
words,<BR>CPU-time: 0.00 seconds.</DIV>
<DIV> </DIV>
<DIV> ITER. STATE ROOT
NORM CORR.ENERGY TOTAL
ENERGY ENERGY CHANGE<BR>
DEN1 VAR(S)
VAR(P) TIME<BR>
1 1 1
1.06866120 0.00000000
-227.20596745 0.00000000<BR> -0.65884541
0.69D-01 0.11D+00 9509.93<BR></DIV>
<DIV> </DIV>
<DIV><STRONG><FONT size=4> Disastrous lack of store,
CIGPS</FONT></STRONG></DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>I was able to run CASPT2 calculations with smaller active space (9,9) where
the number of configurations just sligthly smaller. </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>I will gladly appreciate any suggestions how to override this problem (if
possible). Also I would like to know what causes this problem (lack of disk
space, memory or system swap). </DIV>
<DIV> </DIV>
<DIV>Thanks. </DIV>
<DIV></FONT><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Vadim V.Kislov<BR>Postdoctoral Research
Associate,<BR>Department of Chemistry and Biochemistry,<BR>Florida International
University<BR>11200 SW 8th Street, Miami, FL 33199<BR>e-mail: <A
href="mailto:kvv_bne@mail.ru">kvv_bne@mail.ru</A><BR>tel:
305-348-1945</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV></BODY></HTML>