Vapor Pressures and Heats of Sublimation of Crystalline beta-Cellobiose from Classical Molecular Dynamics Simulations with Quantum Mechanical Corrections
2014 (English)In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 118, no 20, 5365-5373 p.Article in journal (Refereed) Published
In this paper, we report the calculation of the enthalpy of sublimation, Delta H-sub, as a function of temperature of crystalline beta-cellobiose from molecular dynamics (MD) simulations, using two popular carbohydrate force fields. Together with the entropy difference between the solid and the vapor, AS, evaluated at atmospheric pressure, Delta H-sub gives the vapor pressure of cellobiose over the solid phase as a function of T. It is found that when quantum mechanical corrections to the enthalpy calculated from the distribution of normal modes is applied both force fields give Delta H-sub close to experiments. The entropy change, Delta S, which is calculated within a harmonic approximation becomes too small, leading to vapor pressures that are too low. These findings are relevant to MD simulations of crystalline carbohydrates in general, e.g., native cellulose.
Place, publisher, year, edition, pages
2014. Vol. 118, no 20, 5365-5373 p.
Particle Mesh Ewald, Force-Field, D-Glucose, Thermodynamics, Solvation, Entropy, Surface, Water
IdentifiersURN: urn:nbn:se:kth:diva-147037DOI: 10.1021/jp501839kISI: 000336510300009ScopusID: 2-s2.0-84901351130OAI: oai:DiVA.org:kth-147037DiVA: diva2:728487
QC 201406242014-06-242014-06-232014-06-24Bibliographically approved