NEXAFS sensitivity to bond lengths in complex molecular materials: a study of crystalline saccharides

DOI: 10.1021/acs.jpcb.5b07159
PMID: 26459024

Authors: Adrian Gainar (The University of Manchester) , Joanna S. Stevens (The University of Manchester) , Cherno Jaye (National Institute of Standards and Technology) , Daniel A. Fischer (National Institute of Standards and Technology) , Sven L. M. Schroeder (The University of Manchester, Diamond Light Source)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: The Journal Of Physical Chemistry B , VOL 119 (45) , PAGES 14373 - 14381

State: Published (Approved)
Published: November 2015

Abstract: Detailed analysis of the C K near-edge X-ray absorption fine structure (NEXAFS) spectra of a series of saccharides (fructose, xylose, glucose, galactose, maltose monohydrate, α-lactose monohydrate, anhydrous β-lactose, cellulose) indicates that the precise determination of IPs and σ* shape resonance energies is sensitive enough to distinguish different crystalline saccharides through the variations in their average C–OH bond lengths. Experimental data as well as FEFF8 calculations confirm that bond length variations in the organic solid state of 10–2 Å can be experimentally detected, opening up the possibility to use NEXAFS for obtaining incisive structural information for molecular materials, including noncrystalline systems without long-range order such as dissolved species in solutions, colloids, melts, and similar amorphous phases. The observed bond length sensitivity is as good as that originally reported for gas-phase and adsorbed molecular species. NEXAFS-derived molecular structure data for the condensed phase may therefore be used to guide molecular modeling as well as to validate computationally derived structure models for such systems. Some results indicate further analytical value in that the σ* shape resonance analysis may distinguish hemiketals from hemiacetals (i.e., derived from ketoses and aldoses) as well as α from β forms of otherwise identical saccharides.

Journal Keywords: Cellulose; Carbohydrates; Energy; Crystal structure; X-ray absorption near edge spectroscopy

Subject Areas: Chemistry, Food Science


Technical Areas:

Added On: 15/12/2015 15:39

Documents:
acs.jpcb.5b07159.pdf

Discipline Tags:

Chemistry Organic Chemistry Food Science

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