Selecting search parameters for GMIN - Revision history

import>Mp466 at 16:27, 3 August 2009

2009-08-03T16:27:59Z

← Older revision		Revision as of 16:27, 3 August 2009
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	1. The number of '''STEPS''' should be long enough to at least see one conformational change without restarting.		1. The number of '''STEPS''' should be long enough to at least see one conformational change without restarting.

	2. The step size '''STEP''' should be roughly 2/3 of an interaction distance. Longer distances maybe required for the system.		2. The step size '''STEP''' should be roughly 2/3 of an interaction distance for atomic clusters. Longer distances maybe required for the system.

	3. The number of My-LBFGS minisation steps '''MAXIT''' should be large enough so 99% of the steps converge. This promotes more		3. The number of My-LBFGS minisation steps '''MAXIT''' should be large enough so 99% of the steps converge. This promotes more
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	4. The final quenches should be ordered with respect to their energies. If they are not, it means that lower		4. The final quenches should be ordered with respect to their energies. If they are not, it means that lower
	energy structure have been found upon tight convergence and the '''SLOPPYCONV''' needs to be tightened.		energy structure have been found upon tight convergence and the '''SLOPPYCONV''' needs to be tightened. Also if
			the same minimum is being found with the tight convergence it suggests '''SLOPPYCONV''' is not differentiating between
			minima well, and therefore should be tightened as well.

	5. The '''TEMPERATURE''' should be high enough to over come barrier heights., but not so large that all barriers are		5. The '''TEMPERATURE''' should be high enough to over come barrier heights., but not so large that all barriers are

import>Mp466 at 14:20, 3 August 2009

2009-08-03T14:20:57Z

← Older revision		Revision as of 14:20, 3 August 2009
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	There are a few general tips for selecting parameters for geometry optimisation.		There are a few general tips for selecting parameters for geometry optimisation.

	1. The number of STEPS should be long enough to at least see one conformational change without restarting.		1. The number of '''STEPS''' should be long enough to at least see one conformational change without restarting.

	2. The step size ~~depending one ones system~~ should be roughly 2/3 of an interaction distance. Longer distances		2. The step size '''STEP''' should be roughly 2/3 of an interaction distance. Longer distances maybe required for the system.
	maybe required for the system.

	3. The number of My-LBFGS minisation ~~step~~ should be large enough so 99% of the steps converge. This promotes more		3. The number of My-LBFGS minisation steps '''MAXIT''' should be large enough so 99% of the steps converge. This promotes more
	efficient sampling.		efficient sampling.

	4. The final quenches should be ordered with respect to their energies. If they are not, it means that lower		4. The final quenches should be ordered with respect to their energies. If they are not, it means that lower
	energy structure have been found upon tight convergence and the SLOPPYCONV needs to be tightened.		energy structure have been found upon tight convergence and the '''SLOPPYCONV''' needs to be tightened.

	5. The TEMPERATURE should be high enough to over come barrier heights., but not so large that all barriers are		5. The '''TEMPERATURE''' should be high enough to over come barrier heights., but not so large that all barriers are
	overcome thereby causing the rescaling of the move step to result in very large steps which may take a long time to		overcome thereby causing the rescaling of the move step to result in very large steps which may take a long time to
	converge. This is system dependent and requires testing to ensure efficient sampling.		converge. This is system dependent and requires testing to ensure efficient sampling.

import>Mp466 at 14:18, 3 August 2009

2009-08-03T14:18:41Z

New page

There are a few general tips for selecting parameters for geometry optimisation.

1. The number of STEPS should be long enough to at least see one conformational change without restarting.

2. The step size depending one ones system should be roughly 2/3 of an interaction distance. Longer distances
maybe required for the system.

3. The number of My-LBFGS minisation step should be large enough so 99% of the steps converge. This promotes more
efficient sampling.

4. The final quenches should be ordered with respect to their energies. If they are not, it means that lower
energy structure have been found upon tight convergence and the SLOPPYCONV needs to be tightened.

5. The TEMPERATURE should be high enough to over come barrier heights., but not so large that all barriers are
overcome thereby causing the rescaling of the move step to result in very large steps which may take a long time to
converge. This is system dependent and requires testing to ensure efficient sampling.