English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The yardstick of new first-principles approaches to key points on reactionpaths at metal surfaces is chemical accuracy compared to reliable experiment.By this we mean that such values as the activation barrier are required towithin 1 kcal/mol. Quantum Monte Carlo (QMC) is a promising (albeit lengthy)first-principles method for this and we are now beyond the dawn of QMCbenchmarks for these systems, since hydrogen dissociation on Cu(111) has beenstudied with quite adequate accuracy in two improving QMC studies \cite{hog0,kdd2}. Pt and Cu require the use of pseudo-potentials in these calculations andwe show that those of Pt are less problematic than those for Cu, particularlyfor QMC work. This work determines physisorption energies for hydrogen atomsand molecules on Pt(111). These systems are used as asymptotes to determinereaction barriers. As such, they must be referred to clean Pt(111) surfaces andthe isolated hydrogen atom or molecule. Previous work gave the activationbarrier to hydrogen dissociation on Pt(111) using the bridging geometry. Themethod used is state-of-the-art ({\it ab initio}) QMC. This barrier agrees tobetter than chemical accuracy with a recent Specific Reaction Parameter(SRP-DFT) calculation, fitted to measurement \cite{iran}. The results give thedissociation barrier for hydrogen on Pt(111) as 5.4 kcal/mol (QMC and 6.2 bySRP-DFT) with a QMC standard error below 0.99 kcal/mol. This is encouraging forestablishing less well-known benchmark values of industrial reaction barrierson Pt(111).

Quantum Monte Carlo prerequisites for industrial catalysts. Accurately assessing H atom and H$_2$ physical adsorption energy on Pt(111)