We have established a new cellulose modification protocol without any additional catalysts and corrosive chemicals.

Ionic liquids (ILs) are salts with an extremely low melting point. Substantial efforts have been made to address their low melting point from the enthalpic standpoint (i.e. interionic interactions). However, this question is still open. In this study, we report our findings that entropic (large fusion entropy), rather than enthalpic, contributions are primarily responsible for lowering the melting point in many cases, based on a large thermodynamic dataset. We have established a computational protocol using molecular dynamics simulations to decompose fusion entropy into kinetic (translational, rotational, and intramolecular vibrational) and structural (conformational and configurational) terms and successfully applied this approach for two representatives of ILs and NaCl. It is revealed that large structural contribution, particularly configurational entropy in the liquid state, plays a deterministic role in the large fusion entropy and consequently the low melting point of the ILs.

Catching changing boron coordination: Laboratory glassware and kitchen cookware alike are made of glass that contains different cations, including boron, sodium, and aluminum. Properties of glass depend on the number and location of oxygen atoms surrounding each cation. Edwards et al. combine nuclear magnetic resonance measurements with theoretical calculations to understand structural transformations in borosilicate glass (see the Perspective by Youngman). Boron atoms in planar threefold coordination move out of plane with increasing pressure to form trigonal pyramids. Identification of this type of transition state connects structural evolution with stress-induced processes in amorphous materials. In borosilicate glass, the transition leads to the formation of tetrahedral fourfold-coordinated boron that tunes glass properties for use in numerous applications. Science , this issue p. 1027 ; see also p. 998