Customizing Basis Sets

If you want to set up your own .basis file, you can do so, if you use the format described above. Generally, you must also create an altered version of the .atomig file, which is described in The Initial Guess Data File, although if you are just adding polarization functions to the basis set, and these functions are identified by the polarization/diffuse function parameter described earlier in this section, you can continue to use the usual .atomig file. Make sure your new .basis file contains the 6‑31G basis set, because the initial guess program needs this basis set. If you alter the basis functions in the default.basis file only slightly, you can use the same names for the basis sets. If you change them a great deal, you should use a new name, so that Jaguar will not attempt to use grids or dealiasing functions that do not match the new basis set. If you change a basis set name to something Jaguar does not recognize, runs using that basis set will use all-analytic methods (see SCF Accuracy Level or the information on the gen section keyword nops in Keywords for SCF Methods in the Jaguar Input File).

To use the file in a Jaguar calculation, you must add a line in the form

BASISFILE: filename

to the input file for the job. The file name must not include a path, and the file must be in the same directory as your input file.

Note: Any basis sets you add will only be available for non-pseudospectral calculations, because they do not have associated grids and dealiasing functions.