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Q-Chem

Description

Q-Chem is a modern object-oriented quantum chemistry program. A variety of electronic structure methods (Hartree-Fock/SCF ,DFT, MPn, Coupled Cluster) are available. Q-Chem also includes a suite of tools for chemical and spectroscopic properties analysis.

Some of the methods in Q-Chem run only in serial mode - you cannot use these methods with more than one processor. Check the manual carefuly to see if the method you want to use can take advantage of more than one processor or not.

How to Access Q-Chem

NERSC uses modules to manage access to software.  To use the default version of Q-Chem, type:

%  module load qchem

Running Q-Chem on Carver

To run qchem parallel jobs interactively on Carver, you need to request a batch session using qsub -I command.

% qsub -I -V -l nodes=1:ppn=8 -q debug

And when the batch session is retured to you, type,

% cd $PBS_O_WORKDIR
% module load qchem
% qchem -np 8 infile outfile

To run batch jobs, you need to submit a batch script using the qsub command. Here is a sample batch script for Carver:

#PBS -S /bin/tcsh
#PBS -l nodes=1:ppn=8,walltime=2:00:00
#PBS -N qchem_test
#PBS -j oe
#PBS -q regular
#PBS -V

cd $PBS_O_WORKDIR
module load qchem

qchem -np 8 infile outfile

Documentation

Q-Chem 3.1 Manual (PDF)

Q-Chem 3.2 Manual (PDF)

Availibility

PackagePlatformCategoryVersionModuleInstall DateDate Made Default
Q-Chem carver applications/ chemistry 3.2.0.2 qchem/3.2.0.2 2010-06-07
Q-Chem carver applications/ chemistry 3.2.0.2-intel qchem/3.2.0.2-intel 2012-01-13
qchem carver applications/ chemistry 3.2.0.2 qchem/3.2.0.2-intel 2010-10-07 2010-10-14