Influence on the energy of covalent link of the isotopic composition forming its nuclei

In this paper, on the basis of the classical quantum-mechanical approach, an explanation is considered of the physical mechanism of isotope fractionation associated with the predominance of a certain number of neutrons among nucleons and explaining the nonequilibrium accumulation of certain forms of stable isotopes of biogenic elements in heterogeneous systems. The reasons for the detected neutron effect can be: the interaction of the magnetic moments of atomic nuclei and valence electrons, leading to a change in the distance between them, including the effect of the changed distance between atoms on the energy of the covalent bond between the resonant pairs of atoms.