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Convergence problem with Zn6S6 NP when optimized with implicit...
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Agbo Sunday
Convergence problem with Zn6S6 NP when optimized with implicit...
I have ALWAYS problems with convergence to proper minima when using PCM or a similar method for implicit solvent and relatively large systems. Are you expecting the geometries in gas-phase and solution to be very different? Because usually they're not and you can in many cases justify well the lack of implicit solvent (and when needed to calculate any energetic effect connected to solvation, you can always use single-point PCM).
I have ALWAYS problems with convergence to proper minima when using PCM or a similar method for implicit solvent and relatively large systems. Are you expecting the geometries in gas-phase and solution to be very different? Because usually they're not and you can in many cases justify well the lack of implicit solvent (and when needed to calculate any energetic effect connected to solvation, you can always use single-point PCM).
Did you try to lower convergence criterium, scfcon=5, for instance? Then you can run with default values. And... put vshift=1000. Don't ask, once it worked for me :).
Did you try to lower convergence criterium, scfcon=5, for instance? Then you can run with default values. And... put vshift=1000. Don't ask, once it worked for me :).
Well, it seems like you've tried a lot of the usual tricks. The only thing that I can think of to suggest is to include "maxsize=1" in your opt command. It tells Gaussian to take smaller step sizes when looking for a minimum and can be helpful when the surface is really flat around a minimum. It takes longer, but it may just help you find what you're looking for. Good luck!
Well, it seems like you've tried a lot of the usual tricks. The only thing that I can think of to suggest is to include "maxsize=1" in your opt command. It tells Gaussian to take smaller step sizes when looking for a minimum and can be helpful when the surface is really flat around a minimum. It takes longer, but it may just help you find what you're looking for. Good luck!
Dear All, thank you for your advices. I managed to solve the convergence problem using the 'nosymm' keyword in the command line, without any other additions. Best regards, Aleksey.
Dear All, thank you for your advices. I managed to solve the convergence problem using the 'nosymm' keyword in the command line, without any other additions. Best regards, Aleksey.
I have ALWAYS problems with convergence to proper minima when using PCM or a similar method for implicit solvent and relatively large systems. Are you expecting the geometries in gas-phase and solution to be very different? Because usually they're not and you can in many cases justify well the lack of implicit solvent (and when needed to calculate any energetic effect connected to solvation, you can always use single-point PCM).
I have ALWAYS problems with convergence to proper minima when using PCM or a similar method for implicit solvent and relatively large systems. Are you expecting the geometries in gas-phase and solution to be very different? Because usually they're not and you can in many cases justify well the lack of implicit solvent (and when needed to calculate any energetic effect connected to solvation, you can always use single-point PCM).
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Did you try to lower convergence criterium, scfcon=5, for instance? Then you can run with default values. And... put vshift=1000. Don't ask, once it worked for me :).
Did you try to lower convergence criterium, scfcon=5, for instance? Then you can run with default values. And... put vshift=1000. Don't ask, once it worked for me :).
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VOTE
Well, it seems like you've tried a lot of the usual tricks. The only thing that I can think of to suggest is to include "maxsize=1" in your opt command. It tells Gaussian to take smaller step sizes when looking for a minimum and can be helpful when the surface is really flat around a minimum. It takes longer, but it may just help you find what you're looking for. Good luck!
Well, it seems like you've tried a lot of the usual tricks. The only thing that I can think of to suggest is to include "maxsize=1" in your opt command. It tells Gaussian to take smaller step sizes when looking for a minimum and can be helpful when the surface is really flat around a minimum. It takes longer, but it may just help you find what you're looking for. Good luck!
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Dear All,
thank you for your advices. I managed to solve the convergence problem using the 'nosymm' keyword in the command line, without any other additions.
Best regards,
Aleksey.
Dear All,
thank you for your advices. I managed to solve the convergence problem using the 'nosymm' keyword in the command line, without any other additions.
Best regards,
Aleksey.
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