\(\renewcommand{\AA}{\text{Å}}\)

# fix nvt/manifold/rattle command

## Syntax

    fix ID group-ID nvt/manifold/rattle tol maxit manifold manifold-args keyword value ...

- ID, group-ID are documented in fix command

- nvt/manifold/rattle = style name of this fix command

- tol = tolerance to which Newton iteration must converge

- maxit = maximum number of iterations to perform

- manifold = name of the manifold

- manifold-args = parameters for the manifold

- one or more keyword/value pairs may be appended

      keyword = temp or tchain or every
        temp values = Tstart Tstop Tdamp
          Tstart, Tstop = external temperature at start/end of run
          Tdamp = temperature damping parameter (time units)
        tchain value = N
          N = length of thermostat chain (1 = single thermostat)
        every value = N
          N = print info about iteration every N steps. N = 0 means no output

## Examples

    fix 1 all nvt/manifold/rattle 1e-4 10 cylinder 3.0 temp 1.0 1.0 10.0

## Description

This fix combines the RATTLE-based (Andersen) time integrator of fix nve/manifold/rattle (Paquay) with a Nose-Hoover-chain thermostat to sample the canonical ensemble of particles constrained to a curved surface (manifold). This sampling does suffer from discretization bias of O(dt). For a list of currently supported manifolds and their parameters, see the Howto manifold doc page.

## Restart, fix_modify, output, run start/stop, minimize info

No information about this fix is written to binary restart files. None of the fix_modify options are relevant to this fix. No global or per-atom quantities are stored by this fix for access by various output commands. No parameter of this fix can be used with the start/stop keywords of the run command. This fix is not invoked during energy minimization.

## Restrictions

This fix is part of the MANIFOLD package. It is only enabled if LAMMPS was built with that package. See the Build package page for more info.

## Related commands

fix nve/manifold/rattle, fix manifoldforce Default: every = 0

(Andersen) Andersen, J. Comp. Phys. 52, 24, (1983).

(Paquay) Paquay and Kusters, Biophys. J., 110, 6, (2016). preprint available at arXiv:1411.3019.