MMMx represents ensemble structures by sets of weighted conformers. The standard format is an ensemble list
The file starts with a comment line (initiated by a
% character) the reports the name and the date and time of generation.
This is followed by lines ( is the number of conformers in the ensemble) that each contain a PDB file name and a weight.
The weights are considered as populations and thus add up to unity. Ensembles can be archived, by generating a ZIP file that
contains the ensemble list as well as the individual PDB files of the conformers (see
archive keyword in EnsembleAnalysis.