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.