Convergence Error

I get the following error:

psi4.driver.p4util.exceptions.OptimizationConvergenceError: Could not converge geometry optimization in 3 iterations.

    core.set_global_option("REFERENCE", "rks")
    core.set_global_option("S_TOLERANCE", 1e-9)
--> optimize('b3lyp')

I have no idea why it’s stopping at this point.

Look forward to your thoughts.



Please follow the guidelines for posting topics. Without an input file, we cannot possibly help you. Having the output, or at least a Psi4 version number, would make it easier.

Thanks for following up.

The error I was getting was:

TORS::compute_val: unable to compute torsion value

To gain some more insight, I did go back and review older posts and came across:

In short, they had a similar error that may have resulted from dealing with a planar structure.

My solution ultimately was to step back on the basis set (even further) and work my way up to my desired level (B3LYP-D3BJ; aug-cc-pVTZ).

This did solve my issue.