Dissociation free energy profiles for water and methanol on TiO2 surfaces

The umbrella sampling methodology is applied in the framework of density functional theory and Car-Parrinello molecular dynamics simulations to obtain the free energy profiles for the dissociation of methanol and water on stoichiometric TiO2 surfaces. In particular, we study the dissociation of wate...

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Detalles Bibliográficos
Autores principales: Sánchez, V.M., Cojulun, J.A., Scherlis, D.A.
Formato: JOUR
Materias:
Activation barriers
Car-Parrinello molecular dynamics simulations
Entropic contributions
Reaction free energy
TiO
Umbrella sampling
Zero temperatures
Activation energy
Density functional theory
Free energy
Methanol
Molecular dynamics
Oxide minerals
Reaction kinetics
Titanium dioxide
Dissociation
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_19327447_v114_n26_p11522_Sanchez
Aporte de:
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
Descripción
Sumario:The umbrella sampling methodology is applied in the framework of density functional theory and Car-Parrinello molecular dynamics simulations to obtain the free energy profiles for the dissociation of methanol and water on stoichiometric TiO2 surfaces. In particular, we study the dissociation of water on rutile (110) and anatase (101), and the dissociation of the O-H and C-O bonds of methanol on anatase (101). We discuss the reaction free energies and activation barriers of these processes in the light of experiments and previous simulations at zero temperature. The entropic contribution to the reaction free energy is found to be positive for the dissociation of water and negative for the dissociation of methanol. © 2010 American Chemical Society.

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