Way to measure nber of contacts and duration of each contact of a pair of species over a trajectory?

GROMACS version:2019.1, 2018.2
GROMACS modification: No
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Friends,

I have a multi species system trajectory (memb protein).

I want to know,

  1. how many times a pair of atoms or a a pair of two molecules/residues come into contact, bond, non-bond interact (#update: I saw Justin has recommended gmx_mindist for contact count)

  2. how long (time) these contacts, interactions lasts

  3. Is there a mx_something to generate a plot for above measures?

Is there a way to extract this info from trajectory?

If not using gmx_… what alternatives are there to achieve it?

  1. Is there a way to measure tilt of the protein over time? And generate a plot, series of snapshots?

  2. Is there a way to generate a plot of various interactions by a particular atom molecule with neighborhood? (covalent, bonded, non bonded, VDW, H, salts b etc…)

Thank you for ideas, papers, rocks and scissors!!!