Behaviors of H-2-absorption to CuRn+ have been investigated at the CCSD(T) theoretical level. The "T-shaped" H-2-absorption to the Cu or to Rn atom can be found with different binding energies, and it can be characterized by infrared radiation spectrum. The three-atom Cu/Rn center dot center dot center dot H-2 interactions are investigated by AIM theory, topological analysis on electron density function, delocalization index, and independent gradient model analysis. It characterizes the partial covalent character for the Cu center dot center dot center dot H-2 interactions and van der Waals character for the Rn center dot center dot center dot H-2 interactions. Consistencies show the reliability of bond critical point properties for the present three-atom Cu/Rn center dot center dot center dot H-2 interactions due to the very small H H distances. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.