8 Basis Sets

8.2 Built-In Basis Sets

Q-Chem is equipped with many standard basis sets,13 and allows the user to specify the required basis set by its standard symbolic representation. The available built-in basis sets include the following types:

  • Pople basis sets 96, 318, 231, 232, 233, 308

  • Dunning basis sets 439

  • Correlation consistent Dunning basis sets 440, 1004, 1005, 990, 486, 49

  • Ahlrichs basis sets 804

  • Jensen polarization consistent basis sets 421

  • Karlsruhe "def2" basis sets 35, 455, 804, 554, 961, 767

  • The universal Gaussian basis set (UGBS) 214

In addition, Q-Chem supports the following features:

  • Extra diffuse functions available for high quality excited state calculations.

  • Standard polarization functions.

  • Basis sets are requested by symbolic representation.

  • s, p, sp, d, f, g and h angular momentum types of basis functions (For energy calculations up to k are supported).

  • Pure and Cartesian basis functions.

  • Mixed basis sets (see section 8.5).

  • Basis set superposition error (BSSE) corrections.

The following $rem keyword controls the basis set:

BASIS
       Sets the basis set to be used
TYPE:
       STRING
DEFAULT:
       No default basis set
OPTIONS:
       General, Gen User-defined. See section below Symbol Use standard basis sets as in the table below Mixed Use a combination of different basis sets
RECOMMENDATION:
       Consult literature and reviews to aid your selection.