Low-Temperature Thermoluminescent Behavior of 5′dcmp Single Crystals
Document Type
Article
Publication Date
1-1-1982
Description
Thermoluminescence (TL) and emission spectra studies of x-irradiated single crystals of deoxycytidine-5′-phosphate monohydrate (5′ dCMP) were conducted in the interval 10-300 K. Two intense glow peaks were observed at 42 and 74 K with additional weaker peaks at 112, 140, and 200 K. By applying the Randall-Wilkins theory of glow curves to our data we obtained thermal activation energies (E) and frequency factors (s) characterizing each of the glow peaks, except the one at 200 K-it was of insufficient intensity. The parameters are: 42 K (E=0.032±0.009 eV, s=316 s-1); 74 K (E=0.095±0.035 eV, s=105 s-1); 112 K (E=0.080±0.02 eV, 5=20 s -1); and 140 K (E=0.12±0.04 eV, s=56 s-1). As a check on the validity of the Randall-Wilkins theory we generated theoretical glow curves using the experimental parameters of the 42 K peak. Excellent agreement between the two glow curves was found. Typical spectral emission from each glow peak consists of band emission exhibiting maxima at 428 and 463 nm. We attribute these peaks to radiative electronic transitions from the first excited singlet and triplet states to the ground state (S1→ S0+hν and T1→S0+hν). Based upon our experimental results we present an energy-level diagram depicting the TL process in single crystal 5′dCMP in the interval 10-300 K. Finally, we discuss possible correlations between the appearance of TL glow peaks and the thermal decay of radiation-induced radicals as observed by ESR and ENDOR.
Citation Information
Cooke, D. W.; and Close, David M.. 1982. Low-Temperature Thermoluminescent Behavior of 5′dcmp Single Crystals. The Journal of Chemical Physics. Vol.76(5). 2174-2178. https://doi.org/10.1063/1.443288 ISSN: 0021-9606