An illustrative Conceptual Layout and Design of the Instrument
In its simplest form, an NMR spectrometer consists of a strong magnet, an RF transmitter/receiver, shim coils, an RF amplifier, an analog to digital Converter (ADC), and a computer. For use in NMR, the magnet must be able to generate a very strong magnetic field with properties of staticity and homogeneity. In the past, three types of magnets were used to this end: permanent magnets, conventional electromagnets and superconducting solenoids. Today, virtually all high-resolution NMR spectrometers use superconducting solenoids due to their ability to produce very stable and powerful magnetic fields. Furthermore, the operating costs of superconducting solenoids are very low. The material is brought into a superconducting state (zero electrical resistance) by submersion in a bath of liquid helium. The helium itself is then immersed in a bath of liquid nitrogen to prevent helium evaporation.

Fig 1. General overview of a modern NMR spectrometer.

The sample is placed in a glass tub...