In conclusion, we have calibrated an atomically sized thermometer to develop methods to measure local base pair melting with variable temperature TC2=O isotope editing IR of a DNA duplex. We have attributed various atomic contributions in the IR spectrum of the duplexed thymine to the signal at 1720 cm -1 . Most of the amplitude arises from the TC2=O stretch, indicating changes observed from this signal are most likely located at these atoms. Future work will seek to explore the impact of nucleic acid normal modes upon hydrogen-deuterium exchange and determine the thermodynamic parameters, such as the free energies and heats of formations for individual interactions that contribute to motif stability in DNA duplexes with a focus on each of the classic ten different nearest neighbor motifs for the Watson-Crick A-T base pair.