First-Principles Calculation on Dissociation of Hydrogen Molecule in Nickel

Abstract

The behavior of hydrogen in Ni was investigated using the first-principles calculations. It was found that there exists only atomic hydrogen in Ni. The hydrogen resides the octabedron, and the lattice constant expands linearly with the concentration of hydrogen. On the basis of a statistical thermodynamic model, the dependency of hydrogen solubility on temperature in Ni was also investigated, and it was found that magnetization does not favor the dissolution of hydrogen, which is in agreement with the experimental results.