Neutron Drop: Condensation of Neutrons in Metal Hydrides and Deuterides

The possible formation of the neutron drop n_A-Zp_Z composed of N_n = A - Z neutrons and N_p = Z protons in metal hydrides and deuterides is discussed on the basis of experimental facts using the evaporation model of the decay of the compound nucleus. Exotic nuclei and the neutron drop will be formed at a region with a high neutron density in crystals including hydrogen isotopes. Successful explanation of the anomalous nuclear reaction phenomenon in solids by models assuming neutrons in a solid lattice is legitimated.