Movement of a Hydrogen Atom through Interstices in a Diamond-Like Lattice

The behavior of hydrogen atom isotopes in a diamond-like lattice without defects is studied. The movement of the hydrogen atom along the interstices is considered. The collective nature of the movement of the hydrogen atom (and its isotopes) is taken into account, which consists in the fact that any movement of the hydrogen atom is accompanied by reversible displacements of the nearest lattice atoms. To take into account this nature of the movement, local chains are built. As a result, a new one-dimensional Lagrangian is derived, the equations of motion from which lead to a soliton-like solution in the form of a kink - Frenkel-Kontorova soliton. The study of the structure of such a kink and the distribution of displacement velocities in it reveals that the kink formed by tritium moves faster through the lattice than the kinks formed by deuterium and hydrogen.