A brief description of the ZIP archives: =========================================== manuscript electron spreadsheets for metrics, electronics, and energetic analysis EndNote bibliographic library BSSE counterpoise demonstrative example for estimation of the basis set superposition error using the most challenging level of theory (CCSD(T)) with manual set up of each counterpoise calculation step thermochemistry unedited output files for MN15+ calculations used to derive the most adequate formalism to connect molecular calculated and macroscopic measured methane binding energies geometric structures Xmol XYZ files of all structures discussed in the manuscript electronic structures cube files generated for spin density contour plots and electron density difference contour plots Additional information available, please feel free to contact us at szilagyi@montana.edu or nstadie@montana.edu