KINETIC TRAPPING PARAMETERS IN LIFMG,CU,P VIA PROMPT AND RESIDUAL ISOTHERMAL DECAY

The isothermal decay of peak 4 in Ben Gurion University-prepared LiF:M g,Cu,P (SSD-NR) was monitored over an extended range of temperatures f rom 110-degrees-C to 192-degrees-C using both the prompt and residual techniques. Three batches of GR-200 material were also measured using either the prompt or the residual technique. The three batches of GR-2 00 material in both compacted and powdered form yielded essentially id entical values of E and s; E = 1.23+/-0.03 eV and 3X10(10) s-1 < s < 9 x10(11) s-1. The SSD-NR material is prepared in a unique manner which eliminates the high temperature structure at 270-degrees-C and results in a substantially narrower peak 4. For this material significantly d ifferent results are obtained; E = 1.47+/-0.03 eV and 2x10(13) s-1 < s < 10(14) s-1. These results for E and s, obtained by the isothermal d ecay technique, do not agree with previously reported values of E and s for peak 4 in LiF:Mg,CuP determined by 'peak shape' techniques which result in very high and unusual values; E > 2 eV and s > 10(20) s-1. An identical anomaly exists for peak 5 in LiF:Mg,Ti. It appears likely that the trapping structures of peak 4 in LiF:Mg,Cu,P and peak 5 in L iF:Mg,Ti respond differently to isothermal heating than to linear heat ing.