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# improper_style zero command

## Syntax

    improper_style zero [nocoeff]

## Examples

    improper_style zero
    improper_style zero nocoeff
    improper_coeff *

## Description

Using an improper style of zero means improper forces and energies are not computed, but the geometry of improper quadruplets is still accessible to other commands.

As an example, the compute improper/local command can be used to compute the chi values for the list of quadruplets of improper atoms listed in the data file read by the read_data command. If no improper style is defined, this command cannot be used.

The optional nocoeff flag allows to read data files with a ImproperCoeff section for any improper style. Similarly, any improper_coeff commands will only be checked for the improper type number and the rest ignored.

Note that the improper_coeff command must be used for all improper types, though no additional values are specified.

## Restrictions

none

## Related commands

none

improper_style none

## Default

none