Circular dichroism applications

The analysis of a series of chiroptical spectra and recovery of systematic trends in a given set can be carried out in several ways. In the past, the results strongly depended on the spectroscopist s personal experience actually, this was the least objective part of the circular dichroism application. Nowadays, we can rely on general procedures of statistical data treatment like singular value decomposition, factor analysis (especially its first part, analysis of the correlation matrix and the projection of the experimental spectra onto the space of orthogonal components), cluster analysis and the use of neural networks. This field has been pioneered by Pancoska and Keiderling [72-76], and also by Johnson [77] when analyzing the chiroptical properties of biopolymers. 

Exam pies of Vibrational Circular Dichroism Applications 283... 

Keiderling TA (1996) Vibrational circular dichroism - applications to conformational analysis of biomolecules. In Fasman GD (ed) Circular Dichroism and the Conformational Analysis of Biomolecules, pp 555-598. New York VCH. 

Polavarapu PL, Petrovic AG, Zhang P. Kramers-Kronig transformation of experimental electronic circular dichroism application to the analysis of optical rotatory dispersion in dimethyl-L-tartrate. Chirality 2006 18(9) 723-732. 

Lewis J W, Tilton R F, Einterz C M, Milder S J, Kuntz I D and Kliger D S 1985 New technique for measuring circular dichroism changes on a nanosecond time scale. Application to (carbonmonoxy)myoglobin and (carbonmonoxy)hemoglobin J. Rhys. Chem. 89 289-94... 

Xie X and Simon J D 1989 Picosecond time-resolved circular dichroism spectroscopy experimental details and applications Rev. Sol. Instrum. 60 2614-27... 

N. Purdie and H. G. Bnttain, eds.. Analytical Applications of Circular Dichroism, Elsevier, Amsterdam, the Nethedands, 1994. 

The investigation of chiral molecular phenomena, and associated technique development, thus hnds potentially signihcant practical applications to place alongside the fundamental interest of this topic. This chapter will examine the recently investigated phenomenon of photoelectron circular dichroism (PECD) that arises from a dissymmetry in the angular distribution of photoelectrons... 

Nina Berova, Kji Nakanishi, and Robert, Woody, Circular dichroism principles and applications, Wiley-VCH, New York, 2nd ed., 2000. 

Determination of protein secondary structure has long been a major application of optical spectroscopic studies of biopolymers (Fasman, 1996 Havel, 1996 Mantsch and Chapman, 1996). These efforts have primarily sought to determine the average fractional amount of overall secondary structure, typically represented as helix and sheet contributions, which comprise the extended, coherent structural elements in well-structured proteins. In some cases further interpretations in terms of turns and specific helix and sheet segment types have developed. Only more limited applications of optical spectra to determination of tertiary structure have appeared, and these normally have used fluorescence or near-UV electronic circular dichroism (ECD) of aromatic residues to sense a change in the fold (Haas, 1995 Woody and Dunker, 1996). 

Magnetic circular dichroism (MCD) has now become a tool with valuable applications to analytical and structural studies. The MCD spectrum of thiophene is only slightly perturbed by substituents, and this is also expected to be true of the quite similar MCD spectra of selenophene.18 These molecules can therefore be classified as hard chromophores. 

C. Djerassi, Optical Rotatory Dispersion Applications to Organic Chemistry (New York, McGraw-Hill, 1960) L. Velluz, M. Legrand, and M. Grosjean, Optical Circular Dichroism, Principles, Measurements, and Applications (Weinheim, Verlag Chemie, 1965) and G. Snatzke (ed.), Optical Rotatory Dispersion and Circular Dichroism in Organic Chemistry (London, Heyden Son, 1967). 

Figure 7.4 Simplified macroscopic model for cholesteric (a) lateral and (b) top view of left-handed superhehx (photographs display a half-pitch length) composed of left-handed helical screws with pitch-to-diameter ratio much smaller than Jt. (Reprinted with permission of John Wiley Sons from Circular Dichroism—Principles and Applications, 2nd ed., N. Berova, K. Nakanishi, R. W. Woody, Eds., Copyright 2000.)...

Crabbe, P., Applications of Optical Rotatory Dispersion and Optical Circular Dichroism in Organic Chemistry, 1, 93. 

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