Perturbation of finite-lattice spectral levels by nearby nuclear resonances

We consider finite linear or cyclic crystalline structures with molecular cells having narrow prethreshold nuclear resonance. We prove that, if the real part of such a nuclear resonance lies within the energy band (the convex hull of the energy levels) of the crystalline structure arising from a separated molecular level, then there exist molecular crystalline states that decay exponentially in time and the decay rate ΓR(m) of these states in the main order is described by the formula ΓR(m) ≅ 4(Rea/ΓR(n), where a is the value of the residue of the molecular channel transfer function at the nuclear resonance