Nuclear Magnetic Resonance
Nuclear Magnetic Resonance (NMR) was developed by Bloch and Purcell (noble price in physics, 1952). The resonance effect is based on absorption of electromagnetic energy of a nuclear spin in a strong magnetic field.

There are widespread applications of NMR spectroscopy. It is being increasingly utilized for analytical investigations of simple liquid solutions as well as for the determination of structures of complex proteins and DNA fragments. It is even possible to perform NMR spectroscopy on complete organisms, which is used for medical imaging.

The non-destructive observation of NMR spectra of every substance is possible, because nuclei with spin I>0 are naturally occurring in every chemical compound. The structure of the observed NMR spectra is determined by the interaction of the nuclear spins with the external magnetic field and the interaction with neighboring nuclei and electrons. The strength of the interaction is closely related to the nature of the chemical bond and the three-dimensional structure of the molecules or solids and gives therefore detailed insights into the physical and chemical properties of the systems under study.