UPDATE

NAME
UPDATE - Assign parameters for the computation of the Verlet neighbor list

SYNOPSIS
UPDATE   fupdte  rspcut

DESCRIPTION
ORAC computes Verlet neighbor lists the atomic groups of both the solvent and solute. There exist three different neighbor lists: a solvent-solvent, a solute-solute and a solvent-solute list. During the run, the calculation is carried out with a frequency equal to fupdte fs. All the group-group interactions within a radial cutoff of $r_{cut} + rspcut$ are included in the neighbor lists. The dimensions of the three lists are printed at run time. In the ORAC output nnlww, nnlpp and nnlpw refers to the solvent-solvent, solute-solute and solute-solvent neighbor list. The current version of ORAC can also use linked cell in place of the conventional Verlet neighbor list (see command LINKED_CELL).

EXAMPLES
UPDATE 65.0 1.4
Update the neighbor lists every 65.0 fs and use a cutoff of $r_{cut} + 1.4$ Å.

DEFAULTS
UPDATE 100.0 1.0

WARNINGS
The neighbor list cutoff must not be chosen larger than half of the simulation box size. The calculation of the neighbor list is performed by default. Only for solvent-only simulations, if the radial cutoff is equal to half of the box size, the force calculation is carried out without the use of neighbor list. When using r-RESPA the value of rspcut is ignored in the UPDATE directive and is taken as an argument of the last step nonbond command in the MTS_RESPA structured command.