Dear Colleague,

As you are a past user of the DL_MESO mesoscale simulation package I am sending 
you this email to announce the release of version 2.6 of DL_MESO. The new 
version contains a Dissipative Particle Dynamics (DPD) code written in Fortran90 
and a Lattice Boltzmann Equation (LBE) code written in C++. Both codes can be 
run either in serial or in parallel using MPI, and can make use of 
multithreading via OpenMP. An optional GUI written in Java is also supplied.

New features in the DPD code compared with DL_MESO 2.5 include major 
optimisations of force calculations and communications between processor cores, 
reduction of replicated data for non-DPD pairwise thermostatting (Lowe-Andersen, 
Peters and Stoyanov-Groot thermostats), an option to divide up force, localised 
density and Ewald sum calculations among threads using OpenMP, Gaussian charge 
smearing (with the option to eliminate real-space pairwise calculations), 
constant surface area and constant surface tension ensembles with Langevin and 
Berendsen barostats and revisions to output files including column headers in 
CORREL statistical data files. A larger range of utilities to manipulate 
trajectory data (creating configurations, calculating isosurfaces and mesophase 
order parameters, radial distribution functions, end-to-end and gyration radii 
of molecules and dipole moments) is also available.

New features in the LBE code compared with DL_MESO 2.5 include additional 
mesophase interaction algorithms - Shan/Chen with quadratic terms, a local form 
of the Lishchuk continuum-based method and Swift free-energy interactions for 
one and two fluid systems - and a greater range of equations of state for 
fluids, Two-Relaxation-Time collisions, the Equal Difference Method algorithm 
for applying forces to fluids, many bug fixes and optimisations including the 
option to divide up calculations among threads using OpenMP.

The new package is still free to academic users and can be obtained from the 
DL_MESO website at www.ccp5.ac.uk/DL_MESO or via the DL_MESO link on the CCP5 
website (www.ccp5.ac.uk). There you may register for the new version and be 
automatically sent instructions to download, decrypt and unpack the codes. The 
registration form is currently hosted by Google: for those users who cannot 
access it, an alternative form is currently being developed and will shortly go 
live. (In the meantime, please email me directly at michael.seaton@stfc.ac.uk if 
you have any difficulty in accessing the form.)

Many people have contributed to DL_MESO version 2.6 and made suggestions for new 
features and optimisations, although I would particularly like to thank Michael 
Johnston and Leopold Grinberg at IBM for their extensive work in optimising both 
codes.

The future development of DL_MESO is dependent on its users and I would 
encourage users to send any suggestions they may have for new features, new 
subroutines or utilities to add to the DL_MESO codes, simulation example cases 
for LBE or DPD etc. Contributions should be sent to michael.seaton@stfc.ac.uk 
with a description and/or instructions for any input files or program codes/
routines.

I would also encourage users who publish articles using results obtained from 
DL_MESO calculations to cite the package using the journal article: Seaton et 
al., Molecular Simulation, 39 (10), 796-821 (2013). An open-access copy of this 
article is available from STFC’s ePubs repository, which can be accessed via the 
DL_MESO website.

Michael Seaton
2015-11-30