620. Very Short: Setting up ORCA (comp. chem.) on debian jessie

Nothing odd here, but providing instructions is never a bad idea. Note that ORCA is binaries only i.e. no source code. It's one reason why I wouldn't want to rely on it as my main code for computational chemistry. However, I am interested in using it to compare select results from nwchem and g09, especially in cases where g09 and nwchem produce differing results.

Either way,. to download ORCA you need to join the ORCA forum:
https://orcaforum.cec.mpg.de/portal.php

Once you've joined you can go to Downloads and, well, download. I went for https://orcaforum.cec.mpg.de/downloads.php?view=detail&df_id=43

sudo mkdir /opt/orca
sudo chown $USER /opt/orca
cp ~/Downloads/orca_3_0_3_linux_x86-64.tbz /opt/orca
cd /opt/orca
tar xvf orca_3_0_3_linux_x86-64.tbz
cd orca_3_0_3_linux_x86-64
ln -s orca orca_cc

The symmlink is there because debian already has a binary called orca.
And that's that installed. To add /opt/orca/orca_3_0_3_linux_x86-64 to PATH do

echo 'export PATH=$PATH:/opt/orca/orca_3_0_3_linux_x86-64' >> ~/.bashrc

To test, try one of the jobs on https://www.sharcnet.ca/help/index.php/ORCA#Parallel_ORCA_job and run using

/opt/orca/orca_3_0_3_linux_x86-64/orca_cc test.inp

*****************
                                 * O   R   C   A *
                                 *****************

           --- An Ab Initio, DFT and Semiempirical electronic structure package ---

                  #######################################################
                  #                        -***-                        #
                  #  Department of molecular theory and spectroscopy    #
                  #              Directorship: Frank Neese              #
                  # Max Planck Institute for Chemical Energy Conversion #
                  #                  D-45470 Muelheim/Ruhr              #
                  #                       Germany                       #
                  #                                                     #
                  #                  All rights reserved                #
                  #                        -***-                        #
                  #######################################################


                         Program Version 3.0.3 - RELEASE   -
[..]
           ************************************************************
           *        Program running with 2 parallel MPI-processes     *
           *              working on a common directory               *
           ************************************************************
------------------------------------------------------------------------------

[..]
------------------------------------------------------------------------------
                       ORCA ELECTRIC PROPERTIES CALCULATION
------------------------------------------------------------------------------

Dipole Moment Calculation                       ... on
Quadrupole Moment Calculation                   ... off
Polarizability Calculation                      ... off
GBWName                                         ... test.gbw
Electron density file                           ... test.scfp.tmp

-------------
DIPOLE MOMENT
-------------
                                X             Y             Z
Electronic contribution:      0.00000      -0.00000      -0.00000
Nuclear contribution   :     -0.00000       0.00000      -0.00000
                        -----------------------------------------
Total Dipole Moment    :     -0.00000       0.00000      -0.00000
                        -----------------------------------------
Magnitude (a.u.)       :      0.00000
Magnitude (Debye)      :      0.00000


Timings for individual modules:

Sum of individual times         ...       45.891 sec (=   0.765 min)
GTO integral calculation        ...        5.511 sec (=   0.092 min)  12.0 %
SCF iterations                  ...       26.269 sec (=   0.438 min)  57.2 %
SCF Gradient evaluation         ...       13.957 sec (=   0.233 min)  30.4 %
Geometry relaxation             ...        0.154 sec (=   0.003 min)   0.3 %
                             ****ORCA TERMINATED NORMALLY****
TOTAL RUN TIME: 0 days 0 hours 0 minutes 50 seconds 359 msec