Assessment of Two Problems of Specific Reaction Parameter Density Functional Theory: Sticking and Diffraction of H on Pt(111).

It is important that theory is able to accurately describe dissociative chemisorption reactions on metal surfaces, as such reactions are often rate-controlling in heterogeneously catalyzed processes. Chemically accurate theoretical descriptions have recently been obtained on the basis of the specific reaction parameter (SRP) approach to density functional (DF) theory (DFT), allowing reaction barriers to be obtained with chemical accuracy. However, being semiempirical, this approach suffers from two basic problems.

Transferability of the Specific Reaction Parameter Density Functional for H + Pt(111) to H + Pt(211).

The accurate description of heterogeneously catalyzed reactions may require chemically accurate evaluation of barriers for reactions of molecules at the edges of metal nanoparticles. It was recently shown that a semiempirical density functional describing the interaction of a molecule dissociating on a flat metal surface (CHD + Pt(111)) is transferable to the same molecule reacting on a stepped surface of the same metal (Pt(211)). However, validation of the method for additional systems is desirable.

Saccade-vergence properties remain more stable over short-time repetition under overlap than under gap task: a preliminary study.

Under natural circumstances, saccade-vergence eye movements are among the most frequently occurring. This study examines the properties of such movements focusing on short-term repetition effects. Are such movements robust over time or are they subject to tiredness? 12 healthy adults performed convergent and divergent combined eye movements either in a gap task (i.