Since pore water in clays can reach pressures below ambient of up to pF 7 it seems possible that using D2O in clay could be a candidate for cold fusion.
Using the deuterium as heavy water rather that individual atoms seems more likely to be successful.
To draw an analogy, individual deuterium atoms are like pairs of wild horses charging around all over the place. An encounter with a second pair at the right orientation for the magnetic field to overcome the coulomb barrier has a low probability of success. Also, because the process is random there is a possibility of generating higher bursts of energy which are damaging.
Coupling the horses to the oxygen carriage means that the orientation can be controlled. Encounters are no longer random but can be organised by channeling the heavy water molecules along streamlines in the high pF regions between the clay minerals.
To achieve this one needs to choose the clay mineral which give the pore water a linear structure, i.e that of the ice vapour pressure phase which has the equation of state:
P = (((V)4)4)4
As you can see, the vapour in this state is under the first three orders of reduced Casimir compression.
