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 [105].

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
tested on master
RANDOM_EXCHANGES 
t: TORSION 
ATOMS
the four atoms involved in the torsional angle
=1,2,3,4 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

Here is plumed.1.dat

Click on the labels of the actions for more information on what each action computes
tested on master
RANDOM_EXCHANGES 
t: TORSION 
ATOMS
the four atoms involved in the torsional angle
=2,3,4,5 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

Here is plumed.2.dat

Click on the labels of the actions for more information on what each action computes
tested on master
RANDOM_EXCHANGES 
t: TORSION 
ATOMS
the four atoms involved in the torsional angle
=3,4,5,6 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
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