ATC: fix_modify AtC decomposition

# fix_modify AtC decomposition

## syntax

fix_modify AtC decomposition <type>

- <type> =
  replicated_memory: nodal information replicated on each processor
  distributed_memory: only owned nodal information on processor

## examples

`fix_modify atc decomposition distributed_memory`

## description

Command for assigning the distribution of work and memory for parallel runs.

## restrictions

replicated_memory is appropriate for simulations were the number of nodes << number of atoms

## related

## default

replicated_memory