CFOUR_NEGEVAL

Specifies what to do if negative eigenvalues are encountered in the totally symmetric Hessian during an NR or MANR geometry-optimization search. If ABORT (=0), the job will terminate with an error message; if SWITCH (=1) the program will just switch the eigenvalue to its absolute value and keep plugging away (this is strongly discouraged!); and if RFA (=2), the keyword CFOUR_GEO_METHOD is switched to RFA internally and the optimization is continued. Psi4 Interface: Geometry optimizations run through PSI (except in sandwich mode) use PSI’s optimizer and so this keyword has no effect. Use optking keywords instead.

• Type: string

• Possible Values: ABORT, SWITCH, RFA

• Default: ABORT