Hi. Thanks Alessandra.
I used this command: gmx mindist -f md.xtc -s md.tpr -n index.ndx -d 0.6 -group
And I selected two groups. But I obtained only 1 output file (mindist.xvg) containing distance info and without info about number of contacts.
In the online manual, I saw:
gmx mindist computes the distance between one group and a number of other groups. Both the minimum distance (between any pair of atoms from the respective groups) and the number of contacts within a given distance are written to two separate output files.
How to resolve it?