RANDOM_EXCHANGES

This is part of the generic module

Set random pattern for exchanges.

In this way, exchanges will not be done between replicas with consecutive index, but will be done using a random pattern. Typically used in bias exchange [88].

Examples

Using the following three input files one can run a bias exchange metadynamics simulation using a different angle in each replica. Exchanges will be randomly tried between replicas 0-1, 0-2 and 1-2

Here is plumed.0.dat

Click on the labels of the actions for more information on what each action computes

RANDOM_EXCHANGES The RANDOM_EXCHANGES action with label 
t: TORSION 
ATOMS
the four atoms involved in the torsional angle 
=1,2,3,4 The TORSION action with label t calculates a single scalar value
METAD 
ARG
the input for this action is the scalar output from one or more other actions. 
=t 
HEIGHT
the heights of the Gaussian hills. 
=0.1 
PACE
compulsory keyword 
the frequency for hill addition 
=100 
SIGMA
compulsory keyword 
the widths of the Gaussian hills 
=0.3 The METAD action with label 

Here is plumed.1.dat

Click on the labels of the actions for more information on what each action computes

RANDOM_EXCHANGES The RANDOM_EXCHANGES action with label 
t: TORSION 
ATOMS
the four atoms involved in the torsional angle 
=2,3,4,5 The TORSION action with label t calculates a single scalar value
METAD 
ARG
the input for this action is the scalar output from one or more other actions. 
=t 
HEIGHT
the heights of the Gaussian hills. 
=0.1 
PACE
compulsory keyword 
the frequency for hill addition 
=100 
SIGMA
compulsory keyword 
the widths of the Gaussian hills 
=0.3 The METAD action with label 

Here is plumed.2.dat

Click on the labels of the actions for more information on what each action computes

RANDOM_EXCHANGES The RANDOM_EXCHANGES action with label 
t: TORSION 
ATOMS
the four atoms involved in the torsional angle 
=3,4,5,6 The TORSION action with label t calculates a single scalar value
METAD 
ARG
the input for this action is the scalar output from one or more other actions. 
=t 
HEIGHT
the heights of the Gaussian hills. 
=0.1 
PACE
compulsory keyword 
the frequency for hill addition 
=100 
SIGMA
compulsory keyword 
the widths of the Gaussian hills 
=0.3 The METAD action with label 

Warning

Multi replica simulations are presently only working with gromacs.

The directive should appear in input files for every replicas. In case SEED is specified, it should be the same in all input files.

Glossary of keywords and components

Options

SEED	seed for random exchanges