Magneto-optical rotation

Magneto-Optic Kerr Rotation Surface Magneto-Optic Kerr Rotation... 

When determining the degree of branching of hydrocarbon mixtures by means of physical constants, especially those physical constants or functions thereof should be chosen that show the necessary sensitivity to the presence of branchings. Particularly the parachor and the magneto-optical rotation have found application. 

The molecular magneto-optical rotation D is a function of the refractive index n, the density d, the Verdet constant V and the molecular weight M ... 

Equation (57) shows the relation between (p and both the molecular magneto-optical rotation D and the molecular refraction rmoi., although rmoi. is much less influenced by the presence of branchings ... 

Natural optical activity is based on the structure of the molecules (optically active centres). Artificial optical rotation is found in magnetic fields the Faraday-Verdet effect or Magneto-Optic Effect, discovered by Michael Faraday in 1845. The theoretical basis for this effect was developed by James Clerk Maxwell in the 1860s and 1870s. From investigations on small molecules we know that the study of magneto-optical rotation offers interesting correlations with the chemical structure and that additive properties of the Verdet constant have been found. 

Optical rotatory dispersion and circular dichroism (83, 84) can often be of great value, and the spectra are particularly sensitive to the conformation of the protein. Much work remains to be done in this field before the results can be definitely interpreted in terms of the electronic structure of the metal. Magneto-optical rotation and magnetic circular dichroism (MOR and MCD), which are beginning to be applied to porphyrins and haemoproteins, offer much greater promise (30, 85). 

Values of the magnetic rotation, p(P—H), which vary markedly with the s -character of the P—H bond have been obtained from a magneto-optical study of compounds in the series PH X3 n, OPH X3 n, and SPHnX3 (X= R or OR R = Me, Et, Pr, Pr , or Bu").200 The barriers to internal rotation and the dipole moments of a number of methyl derivatives, including MePH2 and MeSiH3, have been investigated by semi-empirical M.O. calculations.201... 

Via a magneto-optic effect, the (-)-form of an optical isomer rotates the plane of polarization of a beam of polarized light that passes through a quantity of the material in solution counterclockwise, the (+)-form clockwise. It is due to this property that it was discovered and from which it derives the name optical activity. The property was first observed by J.-B. Biot in 1815, and gained considerable importance in the sugar iiidustrx. analytical chemistry, and pharmaceuticals. 

The use of Faraday rotation spectroscopy to study high Rydberg members and to measure their / values is a recent development. Little early work was done on magneto-optical effects in the vacuum ultraviolet, which can only be explained in terms of technical difficulties, since the subject is not intrinsically new. 

Magneto-optical rotation (MOR) has a long history, stretching back as early as the work of Faraday [152] and Macaluso and Corbino [153], who related MOR to the Zeeman effect [154] well before the advent of quantum mechanics. The Zeeman effect is much used in classical spectroscopy for the determination of J values and g factors, and this is discussed in many standard texts. 

Magneto-optic rotation Electro-optic effects ... 

Fig. 4.8. Basic geometry for the observation of the dispersed Faraday effect the polariser P is crossed with an analyser A, and propagation along an axis Oz is parallel to the field lines B in the region of the atomic absorption cell. Rotation of the plane of polarisation through an angle (p occurs as a result of magneto-optical birefringence (after J.-P. Connerade [161]).

---