Heterospectral correlation

According to Eq. (5.14), covariance transformations can be applied to any type of spectral data sets that are connected to each other by a common history or domain. The spectra thus generated represent heterospectral correlation maps. In NMR spectroscopy, this concept was taken up as unsymmetrical indirect covariance (UIC) NMR, relating, for example. 

Two-dimensional correlation spectroscopy is used for detailed band assignment work. The technique allows spectral information to be analyzed that is much richer in information content than one-dimensional data. Cross-correlation analysis methods are applied to spectral combinations of NIR with NIR, or NIR and mid-infrared, allowing band assignments to be more easily accomplished. An excellent review paper describing the mathematics used in 2-D correlation spectroscopy along with several examples of generalized 2-D NIR and 2-D NIR-mid-infrared (MIR) heterospectral correlation analysis are introduced with 42 references by Ozaki and Wang. °... 

So-called heterospectral correlation, i.e., the investigation of correlation among bands in two different types of spectroscopy, for example, the correlation between NIR bands and mid-IR bands... 

Generalized 2D NIR correlation spectroscopy has been appUed to study, for example, temperature-dependent spectral variations of various compounds such as A-methylacetamide (NMA) (34) and nylon 12 (29), concentration-dependent spectral changes in milk (18) and protein solntions at various temperatures (35, 36), composition-dependent spectral changes in polymer blends (37), and depth-dependent spectral variations of a polymer film (38). Examples of heterospectral correlation are 2D NlR-mid IR heterospectral correlation analysis of nylon 11 (39) and 2D NIR-Raman correlation analysis of polymer blends (40). 

Choi HC, Jung YM, Noda 1, Kim SB (2003) A study of the mechanism of the electrochemical reaction of Utfaium with CoO by two-dimensional soft X-ray absorption spectroscopy (2D XAS), 2D Raman, and 2D heterospectral XAS-Ramtm correlation analysis. J Phys Chem B 107(24) 5806-5811. doi 10.1021/jp(B0438w... 

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