The aim of this research was to analyze the reaction of deuteron fusion, catalyzed by the plasmons in lattices with a cubic structure, to varying the temperature. The probability of fusion in pure and impure palladium metal is calculated using a hypothesis that suggests a kind of chain reaction within the crystalline lattice. As a consequence of the enhanced tunneling effect due to increasing the temperature and the concentration of impurities, this chain reaction would be favored by microcracks formed in the structure as a result of lattice deformation. This paper interprets the results obtained, considering the trend of the potential that describes the effective interaction between deuterons within the metal. In effect, the coupling of plasmons and deuterons, in the presence of impurities, can not only reduce the thickness but also lower the height of the Coulomb barrier K.