Used as a deuterated solvent in nuclear magnetic resonance (NMR) spectroscopy, enabling clearer analysis of proton environments in organic molecules by eliminating interfering signals from non-deuterated solvents. Its deuterium atoms provide a lock signal for the NMR instrument, improving spectral stability and accuracy. Commonly employed in structural elucidation of complex organic and pharmaceutical compounds where high-resolution spectra are required. Also utilized in kinetic and mechanistic studies involving hydrogen-deuterium exchange reactions.