Notes on Options

Note

The options referred to in the Theoretical Methods: SCF to FCI section below and indexed in Keywords by Module are placed in set blocks as described in Job Control, not as arguments to a Python function (like energy()).

Note

All PSI4 keyword names and values are insensitive to case, both those that are placed in set blocks and as Python function arguments. The few exceptions are documented for the database() function, where case structure must match the database file.

Note

Boolean options can be specified by yes, on, true, or 1 for affirmative and no, off, false, or 0 for negative, all insensitive to case.

Note

Certain convergence and tolerance keywords, of type double (real numbers), may be specified using either a real number or an integer; and integer X is then treated as the number of converged decimal digits required. For example, to request as energy converged to , the user may set the e_convergence keyword to 0.000001, 1.0e-6, or 6.