Hydrogen interaction with dissolved atoms in metal solid solutions

The H(D) atom's interaction with one another, other “heavy” interstitial atoms (O, N, and C), and substitutional atoms is analyzed on the basis of strain-induced (elastic) interaction. The interaction energies are calculated for bcc, fcc, and hcp metal solid solutions with regard to the discrete atomic structure of the host lattice. In all cases, the coordination shells of both types - with attraction and with repulsion - exist. The interaction energy dependence on the distance is due mainly to the crystal lattice type. The H-H strain-induced interaction energies are compared with the available literature data from first principle calculations. The strain-induced interaction should be supplemented by repulsion in the nearest coordination shells for the case of interstitial-interstitial interaction and by chemical interaction in the case of H-substitutional interaction. The examples are given for the use of the strain-induced interaction energies in calculations of the long-range order and relaxation processes.