DL_MONTE is a general purpose parallel Monte Carlo simulation package. The software has seen two major development phases up to now. 

DL_MONTE-1 code was originally developed at Daresbury Laboratory by Dr John Purton under the auspices of EPSRC for the Collaborative Computational Project for the Computer Simulation of Condensed Phases (CCP5), and focused primarily on applications in materials science. 

Since 2015 a research grant (EP/M011291/1) obtained from the EPSRC’s Software for the Future programme by Profs. Nigel Wilding (Physics, University of Bath), Steve Parker (Chemistry, University of Bath) and John Purton (Daresbury Laboratory) has funded the further, second developement phase - the DL_MONTE-2 project (as CCP5 Flagship). 

The goal of the DL_MONTE-2 project is to convert DL_MONTE into a truly general purpose Monte Carlo (MC) engine, and to provide an MC simulation software that is inexpensive, accessible and sufficiently generalised to be used in broad academic research. That is, registered users have direct access to the source code for inspection and modification. In the spirit of the enterprise, contributions in the form of working code are welcome, provided the code is compatible with DL_MONTE-2 in regard to its interfaces and programming style and it is adequately documented.

One of the objectives of DL_MONTE-2 is also to provide an alternative (Monte Carlo) methodology for users of DL POLY. Therefore, experience of using DL_POLY would be advantageous for the user, as the DL_MONTE-2 I/O interface and overall workflow is very similar, albeit not identical, to that of DL_POLY. For example, the input to both programs is arranged via three compulsory input files: CONFIG, CONTROL and FIELD. DL_MONTE-2 also uses the same internal units as DL_POLY. 

Latest Release

version 2.03 uploaded 12th Feb 2017
latest patch uploaded 20th April 2017
next release due in mid October 2017

Obtaining DL_MONTE-2

DL_MONTE can be obtained free of charge from CCPForge. You will be required to register for a CCPForge id (if you do not already have one) and then request to join the DL_MONTE-2 project. One of the administrators will then accept your request. 

NOTE: Use of the DL MONTE 2 package without charge is confined to academic research only. Commercial use can only be permissible following negotiation with Daresbury Laboratory (STFC). Users are not allowed to redistribute the program in any form to third parties.

Access DLMONTE project on CCPForge (opens a new tab/window)

Make sure you subscribe to DL_MONTE-2 by clicking on the "Request to join the project" button under the Activity graph on the right-hand side in the main project's webpage on CCPForge)!
- We will only use the information stored to send out the occasional email about DL_MONTE-2, e.g. new releases.


The main features and advanced MC methodologies available in DL_MONTE-2 are outlined below. The list is non-exhaustive as the MC engine functionality is constantly being extended. For details please refer to the DL_MONTE-2 manual.

Statistical Ensembles

Bulk (XYZ PBC):
Canonical - NVT
Isobaric-isothermal - NPT
Grand Canonical - µVT
Semi-Grand Canonical

Planar nanopore (XY PBC):
NVT, µVT and NpT (isotension ensemble)

Force Fields

The availability of force fields in DL_MONTE-2 is determined by the supported interatomic and intramolecular interaction potentials. Like in DL_POLY, the molecular topology and force field parameters are specified in a separate input file (FIELD). The main types of implemented interations are listed below (see also the manual).

Electrostatics - direct, Ewald summation, long-range MFA correction in planar slit geometry
Two-body - a set of bonded and non-bonded potentials
Three-body - a set of bonded and non-bonded potentials
Four-body - bonded: proper and improper dihedrals/torsions
Metals - Sutton/Chen, Gupta and EAM
User-defined - analytic and tabulated

The above set of interactions allows to set up a system with the following force-fields: CHARMM, AMBER, OPLS, Gromos as well as simplified (coarse-grained) models. Support of DL_MONTE-2 by the FIELD creation helper utility DL_FIELD is the work in progress currently. 

Free energy difference (FED) methods

Umbrella sampling – harmonic or tabulated bias
Expanded/extended ensemble – iterative bias optimisation
Wang-Landau scheme – on-the-fly bias optimisation
Lattice/Phase-switch Monte Carlo – FED between two phases

Scenarios beyond conventional MC simulation

FED along volume in NpT ensemble
FED along the centre-of-mass separation for two atomic groups
FED in a range of temperatures or inverse temperatures (β)
Parallel replica-exchange in a range of temperatures (no FED) 



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