Radial (1) and angular (2), (3), and (4) interaction energy diagrams (E_int) of R27 (black) and R28 (orange) entrance channels. (1) Upright blue bar represent R at the equilibrium. (2) Dotted lines illustrates the entrance energy curve of the angular β anisotropies. Molecular energies were calculated at CCSD(T)-F12/cc-pVTZ-F12, units in kcal mol⁻¹, angles in sexagesimal degrees, and molecular distances in Å.