Circular Dichroism (CD) and Magnetic Circular Dichroism (MCD)
For reasons given in Chapter 7, ultraviolet and visible light absorption measurements offer very little information of a selective nature. Two other methods which use light in this wavelength range, optical rotatory dispersion (ORD) and circular dichroism (CD), provide evidence of a structural/stereochemical nature, although to gain such insight it is necessary to compare the results from ORD and CD with information from other methods. When the sample under investigation is subjected to an intense magnetic field (-50 kG) the phenomena observed in ORD and CD are extended, respectively, to magnetic optical rotatory dispersion (MORD) and magnetic circular dichroism (MCD). This chapter is concerned mostly with MCD. However, before attempting a discussion of MCD it will be necessary to first present a brief account of the basic characteristics of the related methods (Djerassi et al., 1971; Stephens, 1974).
KeywordsCircular Dichroism Magnetic Circular Dichroism Cotton Effect Blue Copper Protein Intense Magnetic Field
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