Neutron Crystallography, Molecular Dynamics, and Quantum Mechanics Studies of the Nature of Hydrogen Bonding in Cellulose I β

作者：Yoshiharu Nishiyama, Glenn P. Johnson, Alfred D. French, V. Trevor Forsyth, Paul Langan · 发表于：Biomacromolecules · 年份：2008 · DOI：10.1021/bm800726v · 被引用次数：242 · 研究领域：Advanced Cellulose Research Studies、Lignin and Wood Chemistry、Polysaccharides and Plant Cell Walls

In the crystal structure of cellulose I beta, disordered hydrogen bonding can be represented by the average of two mutually exclusive hydrogen bonding schemes that have been designated A and B. An unanswered question is whether A and B interconvert dynamically, or whether they are static but present in different regions of the microfibril (giving temporally or a spatially averaged structures, respectively). We have used neutron crystallographic techniques to determine the occupancies of A and B at 295 and 15 K, quantum mechanical calculations to compare the energies of A and B, and molecular dynamics calculations to look at the stability of A. Microfibrils are found to have most chains arranged in a crystalline I beta structure with hydrogen bonding scheme A. Smaller regions of static disorder exist, perhaps at defects within or between crystalline domains in which the hydrogen bonding is complex but with certain features that are found in B.