To extract minimum distance distributions (pmin), Radial Distribution Functions (RDFs) and Coordination Numbers (CNs) from the generated MD trajectories, we have used the ALC_TRAJECTORY software, available as open-source (https://github.com/stfc/alc_trajectory). Instructions to download and compile the code are given in such repository. 
The attached SETTINGS file provides an example with the relevant directives to process the MD trajectories.

To execute the code:
1) copy the XDATCAR file to the TRAJECTORY file
2) modify the SETTINGS file accordingly. See instructiones at https://github.com/stfc/alc_trajectory/blob/main/use_code.md 
   a) the &input_composition block must be consistent with the type and the number of atoms. For the Cu/Kapton films the user must corroborate the correct number of Cu atoms.
   b) the &selected_NN_distances block must be set and adjusted to compute pmin between the defined species
   c) the &rdf block must be set and adjusted to compute the RDFs and CNs for the type_a and type_b species. 

The TRAJECTORY and SETTINGS files must be in the same directory.
Information of the analysis is printed to the OUTPUT file. 
