Nuclear magnetic resonance spin angular momentum

In Equation (6) ge is the electronic g tensor, yn is the nuclear g factor (dimensionless), fln is the nuclear magneton in erg/G (or J/T), In is the nuclear spin angular momentum operator, An is the electron-nuclear hyperfine tensor in Hz, and Qn (non-zero for fn > 1) is the quadrupole interaction tensor in Hz. The first two terms in the Hamiltonian are the electron and nuclear Zeeman interactions, respectively the third term is the electron-nuclear hyperfine interaction and the last term is the nuclear quadrupole interaction. For the usual systems with an odd number of unpaired electrons, the transition moment is finite only for a magnetic dipole moment operator oriented perpendicular to the static magnetic field direction. In an ESR resonator in which the sample is placed, the microwave magnetic field must be therefore perpendicular to the external static magnetic field. The selection rules for the electron spin transitions are given in Equation (7)... 

Nuclear magnetic resonance (NMR) spectroscopy is used to study the behavior of the nuclei in a molecule when subjected to an externally applied magnetic field. Nuclei spin about the axis of the externally applied magnetic field and consequently possess an angular momentum. The group of nuclei most commonly exploited in the structural... 

When placed in a static magnetic field of flux density B0, a nucleus may undergo nuclear magnetic resonance (NMR) [1-5] if it possesses an angular momentum p. This angular momentum is referred to as nuclear spin. The component of p in the direction of B0 (Fig. 1.1), denoted as p0, can only take on values which are half-integral or integral multiples m of hj2 n ... 

Before describing the application of Nuclear magnetic resonance (NMR) spectroscopy to potentized homeopathic drugs we would first discuss the basic principles of NMR spectroscopy. This spectroscopy is a powerful tool providing structural information about molecules. Like UV-visible and infra red spectrometry, NMR spectrometry is also a form of absorption spectrometry. Nuclei of some isotopes possess a mechanical spin and the total angular momentum depends on the nuclear spin, or spin number 1. The numerical value of I is related to the mass number and the atomic number and may be 0, Vi, 1 etc. The medium of homeopathic... 

The spin of the nuclei gives rise to nuclear magnetic resonance spectroscopy and there is a corresponding technique, electron spin resonance spectroscopy, arising from electron spin. Photons have a spin angular momentum quantum number of 1. This is the origin of many spectroscopic selection rules. If a photon had no spin, there would be no optical activity... 

In the presence of a magnetic field, the spin angular momentum vector of the proton can take up one of two orientations, just like the electron. This causes two energy levels to be produced, as shown in Figure 5.17. Nuclear magnetic resonance occurs when AE = hv, where vis the frequency of the applied radiofrequency field. 

---