iOpenShell » Q-Chem specific questions » Memory issues in CCSD(T) SP and OPT calculations with QChem

Memory issues in CCSD(T) SP and OPT calculations with QChem

Page: 1

Author Post
Member
Registered: Apr 2016
Posts: 3
I am trying to calculate Correlation energy at CCSD(T)/ cc-pVTZ level (with QChem) but jobs are crashing every time at

"BLOCKING PARAMETERS:
NUM ROCC BLOCKS = 0 NUM AOCC BLOCKS= 2
NUM AVIRT BLOCKS= 23 NUM RVIRT BLOCKS= 0

ORBITALS/BLOCK = 15 14 15 14 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 15 15 15 15 15 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 15 15 15 15 15

BIRREP = A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1 A1" (excerpt from the output file)

which seems a memory issue but it does not make any difference by increasing h_vmem. I don't understand what memory to increase. I have tried some $rem options shown in the input below. Can anyone please see the problem and suggest a solution?

$molecule
0 1
C 4.60034943 -1.85933936 2.94013047
C 4.23844767 -0.15257649 0.65167207
C 5.52965975 2.45088029 0.81745774
C 4.29302311 4.14074898 2.8538456
O 5.52451992 6.54283667 2.89634538
N 8.28079891 2.39056015 1.32091856
C 9.71657467 1.23652339 -0.72620285
H 3.57774282 -3.63672113 2.65763521
H 3.87223792 -0.98919606 4.66811466
H 6.59293318 -2.33137393 3.23069477
H 2.20582056 0.13075015 0.36186364
H 4.91512108 -1.15532184 -1.02976847
H 5.25818205 3.42507195 -0.99562109
H 4.45982933 3.32193065 4.74442196
H 2.29015899 4.45236492 2.44436073
H 7.29388952 6.15561295 2.50961304
H 8.62514496 1.430655 2.95825291
H 9.36019135 2.19147754 -2.52660155
H 9.29688549 -0.77669632 -0.92844135
H 11.73512363 1.41446006 -0.32250068
$end

mol_ID: qm7_4434

$rem
JOB_TYPE = SP
BASIS = cc-pVTZ
EXCHANGE = HF
CORRELATION = CCSD(T)
MAX_SUB_FILE_NUM = 200
AO2MO_DISK = 30000
MEM_TOTAL = 4400
MEM_STATIC = 2400
$end
Member
Registered: Apr 2016
Posts: 3
A little more information, the number of basis functions are 364 which is a pretty big number. It could be an actual problem/challenge.
Member
Registered: Apr 2016
Posts: 3
I am still looking for the solution , could anyone please help ?

Page: 1

iOpenShell » Q-Chem specific questions » Memory issues in CCSD(T) SP and OPT calculations with QChem