It is recommended to put deuterat between 10 and 15 mg of sample in 0.66 mL of solvent for putting the sample in the tubes of RMN.

In order to request the analysis of a sample for RMN, you have to get yourselves with the staff responsible for the team in touch.

You will need to give the toxicity and any storage precautions. Once the report has been delivered, if you do not collect the sample within one week, any remaining sample will be destroyed.

The physical foundation of the spectroscopy of RMN is in the magnetic properties of the atomic core. The interaction of the magnetic moment of a core with an external magnetic field brings about a split of the energetic levels. Transitions can be generated among these different states and the absorption of energy can be detected and record like a spectral line, signal renown of resonance. In this way, spectres can be obtained from compounds that contain atoms the cores of which have magnetic moments different of zero. Among these they find themselves the ¹H, ¹⁹F, ¹⁴N and ¹⁵N and others of interest in chemistry. The core of ¹²C, of great importance in organic chemistry, shows too atomic and even atomic numbers and, therefore, it does not show magnetic moment. Thus, the studies of RMN of C limit themselves to the isotope ¹³C, that it only shows a natural abundance of the 1,1%.

Of a spectre of RMN we can extract three basic data that have to be useful to us for being able to determine the structure in dissolution of our molecule:

1. The position of the signal (chemical displacement, δ). Different signals of resonance for the different protons of the molecule turn up because these protons have different chemical environments.
2. Not all the simple sleep lines (singlets) but some split into doublets, triples, quadruplets or other multiplicities. This split is due to the spin-spin coupling. And it gives us idea about the system about coupling.
   
3. The area under a signal is related with the number of ¹H that they cause the signal and can be measured through integration. Also be necessary to take into account that spectres of other cores can be made, as ¹³C, ³¹P, ¹⁵N, etc, and applying techniques of two-dimensional correlation, special techniques that allow to record spectres in two independent dimensions of frequency. In many experiments an axis of frequency contains chemical displacements and the other one, constants of coupling.
   

They can also contain frequencies of a single core (homonuclears) or of different cores (heteronuclears). This type of experiments is important for the analysis of complex spectres with a great overlap of signals and allow the study of systems as complex as the natural products, biopolymers, proteins or nucleic acids.

1. Determination of structures

The correlations between the chemical displacement or the spin-spin coupling and the structure of the compounds form the basis of the application of the RMN to the determination of unknown compounds structures. Thus, the chemical displacement allows to know the chemical environment in which a core is placed and the integration allows to extract conclusions related to the number from present cores. The spin-spin coupling allows to define the relative positions of the cores, given that the magnitude of the interaction spin-spin (constant of coupling, J) depends of the number and types of links that sort out the different cores.

2. Study of dynamic processes. Study of fast reversible reactions

Another application of the spectroscopy of RMN derives from the observation of the fact that the spectre of RMN of many compounds depends on the temperature. That is, the form of the signal of RMN depends on dynamic processes and on the speed in which these processes take place. Therefore, the spectroscopy of RMN can be used for the study of fast reversible reactions that cannot be followed with the classical kinetic methods.

3. Study of reaction mechanisms

Moreover, the spectroscopy of RMN is also useful for the study of reaction mechanisms in all the branches of the chemistry. In these experiments isotopes of the hydrogen are used, carbon or nitrogen (²H, ¹³C, ¹⁵N) for the follow-up of an atom in particular during the reaction of interest.

4. Interest in other scientific areas

In organic and biochemical chemistry, the spectroscopy of RMN of ¹³C plays a fundamental role, although the ¹⁹F, ¹⁵N and ³¹P also give very valuable information. In inorganic chemistry, a great number of cores of interest can be used thanks to the fast development of the experimental techniques. Since almost all the elements of the periodic table contain a stable isotope with magnetic moment, the area of utilisation of the spectroscopy of RMN is very extensive, even though the abundance born in a lot of these isotopes is small.

• Services of RMN of the UAB
• Specialised Group of Nuclear Magnetic Resonance (Royal Spanish society of chemistry)