In searching for candidate "usable halo nuclei" that might 'fit the bill' for LENR, there is only one other candidate that has turned up so far - calcium.
By usable, the implication is for mass production of an actual energy device. For instance, lithium has a rare halo isotope, but the cost is outrageous. However, past use of lithium electrolytes in LENR may reflect a putative 'halo nucleus effect' even in a tiny ratio of isotope concentration. Palladium has repute halo nuclei but the cost is even more outrageous. Let's clarify: we are looking for something that has a prayer to make it to market. Nickel is somewhat of an anomaly in the transition metals, with the 64Ni isotope. I haven't found another transition metal that is higher, so it appears to be a singularity in terms of excess neutrons relative to the most stable isotope. The ultimate cost is another issue. Since nickel is soluble and the density spread is so high, then the use of an ultracentrifuge should enrich this isotope at a competitive cost, but is there a better choice for exploiting a halo nucleus? The criterion I am using is that the element should be a proton conductor with a range of isotope stability such that the most stable isotope atomic weight, when compared to the stable isotope with the most neutrons gives a ratio that is near or higher than nickel (11% higher) and the cost should be under $100 per kilogram. This is tedious and I am about two thirds through the periodic table and only calcium has registered as another candidate . but the bad news is that 48Ca is only .18% of natural abundance; however, the good news is it is twenty percent higher in atomic weight than 40Ca, and given the low cost and solubility, it should be able to be enriched to a higher level at a low cost. Based on this, and the past implications that calcium is active in LENR, it would seem to be a decent candidate for use in an electrolyte. Plus it has superconducting properties, which seems to go hand in hand with LENR. If any researcher out there is enamored with the halo nucleus possibilities, and has large resources (riiiiiiiiiiiiiiiiight..) and wants to explore the far fringe of a far-out hypothesis, then my suggestion is using an electrolyte (calcium hydroxide?) which is enriched in 48Ca, perhaps to the range of 10% and a cathode of compressed nickel nanopowder which has been enriched in 64Ni. This would be expensive now, but in a high demand situation and mass production - only a tiny fraction of the cost of palladium, which will surely go over $1000 oz. when the economy improves. Jones From: Roarty, Francis X It looks like 64Ni is available in pure form. http://www.americanelements.com/ni64.html Nickel 64 Metal is one of over 250 stable metallic isotopes produced by American Elements for biological and biomedical labeling, as target materials and other applications. Nickel Metal 64 additionally has special application in the noninvasive measurement of human consumption and absorption. Nickel Metal is also available in ultra high purity <http://www.americanelements.com/Ultra_high_purity_metals&powders.htm> and as nanoparticles <http://www.americanelements.com/Submicron_nano_powders.htm> .
