  A new mechanism of LENR in solids is proposed, which is based on the large
amplitude anharmonic lattice vibrations, a.k.a. intrinsic localized modes or
discrete breathers (DBs). In particular, so called gap DBs, which can arise in
diatomic crystals such as metal hydrides, are argued to be the LENR catalyzers.
The large mass difference between H or D and the metal atoms provides a gap in
phonon spectrum, in which DBs can be excited in the H/D sub-lattice resulting
in extreme dynamic closing of adjacent H/D atoms (~ 0.01 {\AA}) required for
the tunneling through nuclear Coulomb barrier. DBs have been shown to arise
either via thermal activation at elevated temperatures or via knocking atoms
out of equilibrium positions under non-equilibrium gas loading conditions,
employed under radiolysis or plasma deposition methods. The DB statistics in
both cases is analyzed, and an attempt is made to quantify part of the
vibrational problem in terms of electrochemical current or ion flux, connecting
them with external excitation of DBs that act as nano-colliders of deuterons
triggering LENR. Resulting analytical expressions (under selected set of
material parameters) describe quantitatively the observed exponential
dependence on temperature and linear dependence on the electric (or ion)
current. Possible ways of engineering the nuclear active environment based on
the present concept are discussed.
