To whom it may concern,
I'm working on optimizing the molecule using gaussian 16. However, it is suffering from the problem of convergence failure. I attempted optimization several times, but failed to meet the convergence criteria. I tried scf=qc, scf=(maxcycle=1024), and opt=calcfc, but it doesn't converge.
Should I keep restarting and continuing the calculation? Please give me some advice on how to succeed in my job.
Best reagrads
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# opt=calcfc freq td=(triplets,root=1) b3lyp/gen scrf=(cpcm,solvent=to
luene) nosymm guess=(read,save) scf=(qc,maxcycle=1024) geom=check pseu
do=read
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Item Value Threshold Converged?
Maximum Force 0.032489 0.000450 NO
RMS Force 0.003501 0.000300 NO
Maximum Displacement 0.006599 0.001800 NO
RMS Displacement 0.001413 0.001200 NO
Predicted change in Energy=-3.509272D-03
GradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGradGrad
Yoon Junho : Hey, have you tried saving an input from the last optimization step and resubmitting the job?
Also, if your initial structure is unsuitable, you have this convergence failure issue. Maybe, you can modify the initial structure and then try it again.
I hope this gives you some hints.
Can you share your input file, if possible?
Thank you, Mohammadreza Sharghi
Does 'opt=restart' mean resubmit the job?
Currently, opt=restart is being performed in the last optimization step.
I want to compute the optimization of the triplet state. However, convergence failures continue to occur.
What exactly does it mean to modify the initial structure? I've attached the input file. Thanks for your help.
Best reagrads
Hey, sorry I got back to you so late.
I do not use restart for submitting the job again. What I do is, I save an input file from the last step of optimization, then, I run another optimization, to see if this time, optimization will converge.
Modifying the initial structure means changing some of the angles, or coordinates for example, and then running another optimization from scratch.
I hope you've already resolved this issue,
Best,
Mohammadreza Sharghi.
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