I have been struggling with geometry optimization of a prostaglandin molecule (20 carbon atoms). I finally got the optimization, all right. Then I did the Frequency job on the optimized structure (I opened the Optimization job .LOG file scrolled up to the last geometry (highest number) and launched the Frequency job from there). Below is my route line from the .gjf file:
# freq=noraman cphf=noread b3lyp/6-31g(d) geom=connectivity
The Frequency job terminated normally and that's what I got in the Frequency job .LOG file:
Item Value Threshold Converged? Maximum Force 0.000005 0.000450 YES RMS Force 0.000001 0.000300 YES Maximum Displacement 0.013516 0.001800 NO RMS Displacement 0.003867 0.001200 NO Predicted change in Energy=-2.250043D-08
Unfortunately, there is no statement: "Stationary point found", however according to Gaussian manual: "A stationary point is found when the Maximum Force and RMS Force are two orders of magnitude smaller than the thresholds shown, regardless of the values of the displacements."
Is not it just the case? If so, why wouldn't Gaussian kindly state that the stationary point was found?