GAUSSIAN

Gaussian9x/03 is a general-purpose ab initio molecular orbital package for the study of molecular structures, reactions, and much more from Gaussian Inc.
The simplest description of how Gaussian works is that the user creates a data-file (extension .gjf (Windows) or .com (Unix/Linux) which describes a molecular system and specifies what kind of calculations and output are desired.
The user then commands Gaussian to carry out the calculation using that data-file. The form and script, left, allows to produce an input file with the main features which can be modified manually and then submitted to and run with Gaussian.
This form and runscript supports the following features of Gaussian:
  • Single Point Energy
  • Geometry Optimization
  • Transition State Optimization
  • Vibrational Frequencies
  • Optimize + Vibrational Frequencies
  • NMR shifts for 1H and 13C spectra
  • Natural Bonding Analysis
  • Molecular Orbitals
  • Others: to be filled in by user
The user extracts the desired output of the calculation from the output files (.out). The inputform calls an editor which opens the output file automatically, once Gaussian has terminated.
This works with Gaussian94/98/03 on Windows 9x, NT4, 2000, XP.
Note that Gaussian9x/03/W(indows) has a shell offering similar comfort (without a choice of keywords presented in pull-down menus, however) for input and inspection of results.

MOLDEN reads the information from the output files; i.e. the geometry, reaction coordinates, wave functions, density and vibrations are read and displayed.

WebMO, for Unix/Linux machines, embeds Gaussian 9x/03(ask for cgi) in a much more complete way compared to the script above, see one page back

Download

Gaussian98/03 the input and run scripts.
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