Ab initio calculations were performed for several suggested mechanisms of energy transfer between helium metastable particles and neon. Optimized geometries and excited-state energies were calculated for neon excited-state complexes and the convergence properties of the non-additive contributions to the interaction energies were examined. The most probable excitation-transfer mechanism was found to be Hem2 (a3Σ+ u )+Ne → (He2Ne) ∗ r → Ne(2p53s)+2He based on an energy difference of 0.0674 eV between the triplet excited state of Hem2 and the singlet excited state of (HeNeHe) ∗ r. No theoretical evidence was found for the production of neon singlet excited-state complexes other than 20.0858 to 20.4875 eV by the considered two-, three- and four-body models of energy transfer processes. The energy curves of the reactions involving the excited-state complexes (HeNeHe) ∗ r and (HeNe) ∗ r are provided and compared with the previously reported experimental results on the reaction Hem2 (a3Σ+ u )+Ne → (He2Ne) ∗ r → Ne(2p53s)+2He. The relation between the probability of energy transfer and laser activity is discussed. The non-additive contribution to the total interaction energy of the nominated (HeNeHe) ∗ r intermediate complex was found to be negligible, pointing to the possibility of constructing model potentials and simulation of larger systems.