DL_POLY

class DL_POLY

This interface supports energy and gradient evaluations with the open source DL_POLY 5 molecular simulation package

As a MM interface, the options described in MM interfaces are available, as well as the DL_POLY specific options outlined below.

A DL_POLY Theory object can be specified as follows:

my_theory = DL_POLY(frag=..., ff='...', ...)

which would then be called as theory=my_theory in subsequent tasks.

DL_POLY forcefields can optionally be managed using DL_FIELD.

General options

berendsen

(default: (0.5,1.5))

delr

(default: 0.0)

densvar

(default: 20)

dl_field_charges

(default: True) Allows DL_FIELD to overwrite the atomic charges

dl_field_types

(default: True) Allows DL_FIELD to overwrite the atomic forcefield types

equilibration

(default: 10)

ewald

(default: 1.E-6)

input

(default: ('CONTROL','CONFIG','FIELD'))

output

(default: '_dl_poly.out')

potential

(default: False)

print

(default: 2)

rcut

(default: -1.0)

rpad

(default: 0.0)

rvdw

(default: 0.0)

scale

(default: 2)

steps

(default: 20)

stack

(default: 50)

stats

(default: 2)

restart

(default: 'scale')

timestep

(default: 0.000)

Importing biomolecular forcefields

CHARMM forcefields may be imported via the DL_FIELD package (see P450 tutorial).

AMBER forcefields in the PRMTOP format can be imported directly with ChemShell and do not need the help of DL_FIELD, for example:

my_mm = DL_POLY(ff='MY_PRMTOP.top')

Note

An example of importing AMBER forcefields for QM/MM calculations can be found in the test suite (tests/qmmm/mndo-dl_poly/chorismate_mutase.py)