modified on 4 October 2011 at 13:09 ••• 6,117 views

Qmmm method

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(Created page with ' method [method1] [method2] [method3] This directive controls which optimization algorithm will be used for the regions as defined by regions directive. The allowed values a…')
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This directive controls which optimization algorithm will be used for the regions as defined by regions directive. The allowed values are "bfgs" aka driver, "lbfgs" limited memory version of quasi-newton, and "sd" simple steepest descent algorithm. The "bfgs" is the most expensive algorithm and is not recomended for more than 100 particles (this essentially restricts its usage only to "qm" or "qmlink" regions). The "lbfgs" algorithm is recomended for both small and large regions and should be used whenever is possible (in many cases it outperforms "bfgs"). Finally "sd" the most ineficient and slow way to optimize regions, yet it is the only option available for the optimization of solvent regions. The default is to assign "sd" to optimization involving solvent region (if any), and "lbfgs" to all others.
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This directive controls which optimization algorithm will be used for the regions as defined by regions directive. The allowed values are "bfgs" aka driver, "lbfgs" limited memory version of quasi-newton, and "sd" simple steepest descent algorithm. The use of this directive is not recommended in all but special cases. In particular,
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"bfgs" should be used for QM region if there are any constraints, "sd" method should be always used for solvent.

Revision as of 17:24, 12 August 2010

method   [method1]  [method2]  [method3]

This directive controls which optimization algorithm will be used for the regions as defined by regions directive. The allowed values are "bfgs" aka driver, "lbfgs" limited memory version of quasi-newton, and "sd" simple steepest descent algorithm. The use of this directive is not recommended in all but special cases. In particular, "bfgs" should be used for QM region if there are any constraints, "sd" method should be always used for solvent.