Feasibility of D–D Nuclear Fusion Achieved by Chemical Methods: Quantum Chemical Analysis

The conceptual design of fusion power plants began decades ago, and significant breakthroughs have been achieved recently. However, the cost of generating energy through controlled nuclear fusion remains extraordinarily high. Cold nuclear fusion achieved by chemical methods offers an alternative approach to cost reduction, but the poor reproducibility of related experiments has led to scepticism about its feasibility. In this study, quantum chemical calculations involving density functional theory (DFT)/basis set (PBE/def2-SVP), geometry optimization, vibrational frequency calculations and relaxed surface scans were performed to calculate Gamow factors and hence estimate D-D nuclear fusion rates in various chemical systems. These systems included free D₂, D₂-Pd₄₄ clusters, molecular deuterium metal (W, Mo and Cr) complexes, and D₂-nanocarbon materials (graphene, single-walled carbon nanotubes and fullerenes). A free D₂ molecule served as a reference point for comparison with other chemical systems. The calculated results indicate that the palladium cluster and metal complexes cannot facilitate the D-D nuclear fusion, whereas carbon nanomaterials can assist with fusing two deuterons together. Remarkably, D₂ encapsulated within a C₂₀ fullerene can exhibit the D-D nuclear fusion rate around 3000 times faster than free D₂, arising from the compression of the interatomic separation of two deuterium atoms by 11% in a strong and small-sized fullerene cage.