I have a relatively small molecule in a relatively large system. The SCF converges very badly because of this.
The question is how to increase the speed of convergence. I should not decrease the size of this system (which will definitely help) since I have to exclude electrostatic interactions between the cell.
Thanks.
A molecule in a large system. Convergence
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Dr Vitaly V. G. Chaban
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A molecule in a large system. Convergence
Last edited by Dr Vitaly V. G. Chaban on Fri Aug 26, 2011 8:03 pm, edited 1 time in total.
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admin
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A molecule in a large system. Convergence
one of the reasons might be that the box is simply too large. If it is not reasonable to decrease the box size, please also check
--) whether you have an even number of valence electrons. if not, please use ISPIN=2
--) make sure you use the Gamma point only
--) decrease the mixing parameters (incl spin mixing, if you have an unpaired electron)
--) whether you have an even number of valence electrons. if not, please use ISPIN=2
--) make sure you use the Gamma point only
--) decrease the mixing parameters (incl spin mixing, if you have an unpaired electron)
Last edited by admin on Wed Aug 31, 2011 4:26 pm, edited 1 time in total.