ORCA

go back to Main Page, Computational Resources, Computational Codes

The program ORCA is a modern electronic structure program package written by F. Neese, with contributions from U. Becker, D. Ganiouchine, S. Koßmann, T. Petrenko, C. Riplinger and F. Wennmohs. The binaries of ORCA are available free of charge for academic users for a variety of platforms.

ORCA is a flexible, efficient and easy-to-use general purpose tool for quantum chemistry with specific emphasis on spectroscopic properties of open-shell molecules. It features a wide variety of standard quantum chemical methods ranging from semiempirical methods to DFT to single- and multireference correlated ab initio methods. It can also treat environmental and relativistic effects.

How to submit calculations

Hi, finally orca is installed and working in kimik2. For send parallel calculations you must to touch your input file with the number of processors:

       ...
       !     PAL4
       ...

(see page 23 of the manual, you can find it in our software repository http://aliga.iciq.es/fsn)

How to send:

       qs orcaVERSION.QUEUE INPUTNAME.in NMACHINES

where:

       VERSION could be 27 (for version 2.7) or 28 (for version 2.8)
       QUEUE could be cq4m4 or c4m8 or c8m24
       INPUTNAME is the name of your input
       NMACHINES is the number of the machines to use (this parameter have directly relation with ! PALX of the input file)

Input files

Single Point Dispersion Calculation Orca_disp.in

Pay attention!

Pay attention to the fact that it starts counting the atom in the coordinates from 0. I. e. In these coordinates:

C  0.000000    0.000000   -1.550099
Br 0.000000    0.000000    0.426228
H  0.000000    1.038299   -1.872463
H  0.899193   -0.519149   -1.872463
H -0.899193   -0.519149   -1.872463

C will be the atom 0, Br the atom 1, and the H the atoms 2, 3 and 4.

The same attends for the numbering of the orbitals.