Temperature and dose effect in the oscillatory transfer annealing of51Cr3+ in K2CrO4

Radiochromium doped potassium chromate exhibits partly an oscillatory exchange between trivalent and hexavalent states of the⁵¹Cr during isothermal treatment. Thermodynamically dissipative structures created by⁵¹Cr/III/ interstitials give rise to rythmic increase and decrease of the transferred yield to the parent lattice. A temperature effect has been noticed on the oscillations by increasing mainly the frequency while a dose effect increases the frequency for the same temperature and decreases the amplitudes. The last is due probably to the elimination of available⁵¹Cr/III/ interstitials after radiation annealing. The Volterra-Lotka model is used to explain the oscillatory exchange of⁵¹Cr.