Interpretive Near-Infrared Spectroscopy

FIGURE 1.3 Methylene symmetrical stretching of CHj - v. (In this movement the two hydrogen atoms move away from the carbon atom at the same time in the outward movement and approach each other at the same time in the return movement.) 

FIGURE 1.4 Methylene asymmetrie stretching of CHj v. (In this movement, while one hydrogen is moving away from the carbon atom, the other is approaching it.) 

If the molecular group consists of four atoms (e.g., one carbon and three hydrogen atoms), instead of three (e.g., one carbon and two hydrogen atoms), they can have two types of bending symmetrical and asymmetrical. 

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J. Workman, L. Weyer, Practical Guide to Interpretive Near-infrared Spectroscopy. Taylor Erancis, Boca Raton, FL, 2007. 

Practical Guide to Interpretive Near-Infrared Spectroscopy... 

Practical guide to interpretive near-infrared spectroscopy / Jerry Workman and Lois Weyer. p. cm. 

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