  We extend the recently proposed mechanism for inducing low energy nuclear
reactions (LENRs) to a crystal lattice. The process gets a dominant
contribution at second order in quantum perturbation theory. The tunnelling
barrier is evaded due to the presence of high energy intermediate states.
However, the process is found to have a negligible rate in free space due to a
delicate cancellation between amplitudes corresponding to different states. The
delicate cancellation can be evaded in medium in special circumstances leading
to an observable rate. Here we consider this process in a one dimensional
crystal lattice and find that the rate depends strongly on the form of
interaction. We find that for some allowed choices of interactions, the rate is
substantial, while other interactions produce a very small rate.
