Mid-infrared study of deoxycytidine at high pressures: evidence of a phase transition

Room temperature mid-infrared experiments between 600 and 1600 cm(-1) have been performed on crystalline deoxycytidine as a function of pressure up to about 10 GPa. The wavenumbers of most vibrational modes shift to higher values with increasing pressures except for a mode near 840 cm(-1). Assignments for the observed modes are made on the basis of work published in the literature. Several anomalies are noted near 4.7 GPa, suggesting a phase transition. Our results for deoxycytidine are compared to similar measurements on cytidine.