First-principle calculations on the structures and electronic properties of the CO-adsorbed (SnO2)2 clusters

The reaction of pristine and Rh-doped SnO2 clusters with acetone: Application of Evans-Polanyi principle to transition state theory

CONTEXT

Using transition state theory, acetone sensing by pristine and rhodium-doped tin dioxide is discussed. The Evans-Polanyi principle is modified from its original formulation commensurate with the Arrhenius equation to be more suitable for transition state theory. The new formalism for the activation energy replaces enthalpy with Gibbs free energy in the original Evans-Polanyi principle. The new formalism considers reaction entropy, which is not considered previously in Evans-Polanyi principle. Response and response time of interaction of acetone with both pristine and Rh-doped SnO2 clusters is calculated. Variations of response in terms of acetone concentration and temperature are calculated and compared to the experiment. Acceptable agreement between theory and experiment that calls for more comparisons to demonstrate the modified approach.

METHODS

The pristine and Rh-doped clusters and their interaction with acetone are simulated using density functional theory at the B3LYP level. 6-311G** and SDD (for heavy atoms) basis sets are used to optimize the structures examined in the present work. Gaussian 09 program and accompanying software performed the current tasks.