Electrons magnetic moments

The transition between levels coupled by the oscillating magnetic field B corresponds to the absorption of the energy required to reorient the electron magnetic moment in a magnetic field. EPR measurements are a study of the transitions between electronic Zeeman levels with A = 1 (the selection rule for EPR). 

Diffusion coefficient, mobile Electron magnetic moment ... 

Compound CAS Registry Number V anadium valence No. of d electrons Magnetic moment, J/T X 10-23" Color... 

Electromagnetic potential operators, transformation properties, 692 Electronic circuit analysis, 338 Electron magnetic moment anomaly, 722... 

Before formally developing the tensor it is perhaps worthwhile to discuss the various types of interactions which contribute to it. The coupling between nuclear and electron magnetic moments are conveniently divided into those which are isotropic and those which depend on orientation. The former is the result of the impaired electron having a finite probability of being at the nucleus. This type of interaction is termed the contact interaction, and is described by the constant,... 

Many elements and compounds do not present an electronic magnetic moment, but their nuclei possess nuclear magnetic moments. These moments can be used for a magnetic refrigeration as it is done with electronic moments. Also in this case the minimum temperature, now in the microkelvin range, is reached when the spontaneous magnetic... 

The low-temperature limit of magnetic thermometry with paramagnetic salts (see Section 9.9) is given by the ordering temperature of the electronic magnetic moments. Such ordering temperature is around 1 mK (example the CMN thermometer). 

The thermally averaged electronic magnetic moment per molecule, induced by the external magnetic field, can in a general anisotropic case be... 

The relaxivity enhancement of water protons in the aqueous solutions of paramagnetic complexes arises from time fluctuation of the dipolar coupling between the electron magnetic moment of the metal ion and the nuclear magnetic moment of the solvent nuclei (13,14). The dipolar interaction... 

Relaxation induced by super-paramagnetic crystals is moreover complicated by another feature the influence of the electron magnetic moment is modulated by Neel relaxation, which depends on the crystal anisotropy (see Fig. 4). 

The electron magnetic moment may also interact with the local magnetic fields of the nuclear dipole moments of nuclei around it. A single electron centered on a nucleus of spin I will experience 2/ -f 1 different local magnetic fields due to the 27 - - 1 different orientations of the nuclear spin I in the external magnetic field. This interaction, which is of the order of 10 cm. i, causes a hyperfine structure in the EPR spectrum. This structure is further discussed and illustrated in Section III,B. 

It was noted that for 78b and 79b, 7hf and 7cf are dependent on the molecular conformation, but this is not the case with 7nf. which is independent of the conformation. It is well known that the internuclear couplings are electron coupled interactions for which there are three possible mechanisms (1) the nuclear moments interact with the electronic currents produced by the orbiting electrons (2) there is a dipolar interaction between the nuclear and electronic magnetic moments (3) there is an interaction between the nuclear moments and the electronic spins in i-orbitals, the so-called Fermi contact term. ... 

Here gk is the so-called nuclear g-value of the kth nucleus, H is the strength of the applied field, ntip is the mass of the proton, ge is the electron magnetic moment, and c is the speed... 

Table 6.16 Distribution of Electrons and Electronic Magnetic Moments in Some Transition Metals...

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