Dear Colleague,
 
Some minor updates to DL_MESO 2.7 have been made and are now available for 
registered users to download as a revised version of the package (2.7 rev 10). 
You do not need to re-register for this update if you have previously 
registered for an earlier form of version 2.7: the revised package can be 
downloaded from the same location as before and decrypted using the same 
password. If you would like to use version 2.7 but have not yet registered for 
this version (e.g. if you have previously registered for version 2.6), please 
do so via the link from the DL_MESO website at www.ccp5.ac.uk/DL_MESO

This revision makes changes solely to the DPD code and one of its utilities. 
Further changes have been made to the assignment of long-range corrections to 
potentials and virials for Lennard-Jones interactions, which now lead to correctly
reported potential energies, stress tensors and system pressures in OUTPUT and 
CORREL files. (This fix has no effect on the barostats, which had been using 
correctly-calculated instantaneous pressures.) The Widom insertion utility has
also been modified to give correct long-range potential energies for the same 
interaction type, as well as ensuring cutoff distances for many-body DPD, 
short-range electrostatic and surface interactions are correctly used in chemical 
potential calculations. Along with minor updates to the User Manual, README and
Release.md files, this revision now comes with the DL_MESO Technical Manual, which
has been written as a guide for more advanced users and developers on how the codes
work and have been written, including details on file formats and suggestions on 
how the codes can be modified to add additional features, interaction types etc.

Many thanks are due to Vlad Sokhan at UKRI STFC Daresbury Laboratory for 
identifying the long-range corrections bug in DL_MESO's DPD code and the Widom 
insertion utility, and to Rachel Hendrikse at Durham University for identifying and 
suggesting the bug fix for cutoff distances in the same utility.

A new one-stop learning resource for new and current users of DL_Software, 
including DL_MESO, is now available. The DL_Software Digital Guide (DL_SDG) 
includes tutorials, installation information and practical exercises on using 
several DL_Software packages (DL_POLY, DL_FIELD, DL_MESO and DL_ANALYSER), as well 
as a Knowledge Centre providing additional information on modelling methods 
(including the mesoscale methods LBE and DPD). The guide is available at 
https://dl-sdg.github.io/

Michael Seaton
2022-03-21