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Output file notes

    Chemissian currently supports Gaussian, US-Gamess, Firefly/PC-Gamess, Q-Chem and Spartan output files. Below some specific requirements for each supported program output files are presented.

    common note: Use only single-point output files (i.e. without geometry optimization)

  • Notes to Gaussian users:

    • Make sure that your Gaussian input file looks like, e.g.:

    "#P B3LYP/Lanl2dz pop=full GFInput"

    #P option enables extended printout, pop=full enables printout of all molecular orbitals coefficients and GFInput keyword enables printout of basis set data.
    (B3LYP/Lanl2dz are just method and basis set given for example, you can use any other DFT(HF) method and basis set).

    Chemissian uses molecular orbitals coefficients ("EIGENVALUES") section from gaussian output file to build MO energy level diagrams, it is also needed to plot MOs or charge density maps and to describe TDDFT/CIS spectrum peak nature. To plot electron density maps basis set information is also needed. Therefore "GFInput" keyword should be included in the Gaussian input otherwise "Analyze electronic density" menu item will be disabled.

    To visualize calculated TDDFT or CIS UV-VIS spectrum gaussian input file should contain:

    #P B3LYP/Lanl2DZ TD(SINGLETS,NStates=45) Pop=Full gfinput

    B3LYP is just some DFT-method and Lanl2DZ is just some basis (You may choose any other method and basis). Chemissian uses data about molecular orbitals to plot MO diagram, so "#P" and "pop=full" keywords are nessesary. (Later you will also see transitions corresponding to the selected peak (in "Analyze spectrum" window) of tddft-calculated spectrum on this diagram) Also if you want to plot charge densities and MOs contour maps Chemissian need information about basis set use "gfinput" keyword (and gaussian will print basis set). And "TD" is a keyword to calculate spectrum which will be shown when you load gaussian output into Chemissian.

  • Notes to Q-Chem users:

    Specify in Q-Chem input file the following keywords in the $rem section:
    $rem
       print_general_basis=true
       print_orbitals=99999
    $end
    These keywords will force Q-Chem to print LCAO-MO matrix and basis set in its output file.

  • Notes to Spartan users:

    • Use "directory based filesystem" mode in the Spartan program (not .spartan files).
    To enable this mode configure your Spartan in the following way:

    1) Go to Options -> Preferences -> X-Platform
    Select "Directory Based" as the Document Style

    2) Go to Options -> Preferences -> Settings
    Select "Keep Verbose" checkbox.
    Spartan will create a directory for a calculation.

    Now to load Spartan output you just need to click (in Chemissian) "File --> Open…" menu item and select (standard) "output" file. Chemissian will also try to load data from "voutput" file (number of electrons, UV-VIS spectrum) and from "archive" file (basis set data) from the directory where "output" file is located. If these files are missed in the directory (or have other names) Chemissian will ask you to input their location.