Answer
Nuclear Magnetic Resonance (NMR) spectroscopy exploits the magnetic properties of atomic nuclei, particularly those of hydrogen and carbon, to provide detailed information about the structure and dynamics of molecules. Bardeen's contributions to Theory of superconductivity were pivotal in the development of the superconducting magnets used in NMR spectrometers, which generate the high magnetic fields necessary for splitting nuclear energy levels and enabling the detection and analysis of NMR signals.