----- Original Message ---- From: Robin van Spaandonk
> Because Barium is a rather large atom, the valence electrons are far removed from the nucleus, and hence occupy a rather large diameter orbit (Atomic radius = 2.78 Angstrom). When combined with a small atom like oxygen which removes those valence electrons the remaining barium ion is considerably smaller (1.42 Angstrom), hence the increase in density. Yes. And this picture of size variation in the oxide fits in with the notion that the barium nucleus (at least in one isotope), in the properly designed and "conditioned" ferrite core [magnet or transducer] could become artificially distended by several overlapping circumstances - such as the radical change in the Coloumb dynamics of this smaller structure. Since the radius is nearly halved - that indicates upwards to an eight times reduction in volume and that could be what is making the ceramic inherently unstable. They are very easy to break. Certainly, an imposed HV conditioning regime might accentuate the instability. It also brings to mind a possible way to chemically enhance the built-in instability by making one's own ferrites of slightly reduced oxidation level. Since these magnets are presumably made with iron oxide instead of metallic iron powder and since they are presumably fired in air, we might assume that they are fully oxidized. Even if not - I have never seen a manufacturer make reference to trying to accentuate the oxidation state below full. Perhaps using some unoxidized iron powder as a substitute for some of the oxide, and firing them in an anaerobic condition, this would create a built in imbalance in the dynamic of reduced molecular volume - with the free iron constantly "competing" for oxygen, which might make the variability in molecular volume [and corresponding Coulomb dynamics] even greater. Quien sabe? I am putting this on my "to do" list ... [pending winning tomorrow's Lotto] Jones
