  Analysis of kinetic literature suggests several electronic rearrangements
above 600K involving O- (subperoxides) in YBa2Cu3Oy. Slow cooling to 260K
produces a Tc=50K level with conventional plane and cell volume contracted
varieties (P-V-), based on plane oxidizing (4) where (n) denotes local O
coordination. When these materials are quenched from <600K, the subsequent
changes at 298K of structural parameters or Tc have activation energies E=92kJ
and A=1.0x10-12s. The changes saturate at temperatures where they are faster
than the time constant t of quenching. This temperature is extended to 473K
with SQ, indicating t=0.1s. SQ of y near 6.44 from >600K leads to increased
axial ratios, plane and V expansion (P+V+), in a process which is complete near
670 and extending to 950K. P+V+ effects can far exceed P0V0 of the respective
semiconductor. The relative stability at elevated temperatures indicates
another intrinsically slower transformation mechanism of primarily electronic
nature with E=280kJ, involving O-. V+ and its Tc=100K level, is ascribed to (3)
with doped charge on apical O-, acting as a plane expander and n-doper. Similar
slowing of kinetic through O- also hold for the more complex range of Tq>950K.
It can produce a c-axis contracted non-superconductor (P+C-) and indications
for elevated temperature superconductivity (ETS) with Tc>150K*. Kinetic data
are embedded into general thermodynamic arguments concerning peroxide stability
belts.
