Used primarily as a solvent in NMR spectroscopy due to its deuterium content, which provides a non-interfering signal in the analysis of organic compounds. It is also employed in the synthesis of deuterated compounds, where it serves as a source of deuterium atoms. In research, it is utilized for studying reaction mechanisms and molecular structures by replacing hydrogen with deuterium to trace chemical pathways. Additionally, it finds application in the preparation of specialized chemicals and pharmaceuticals where isotopic labeling is required for tracking or stability studies.