(617cq) Benchmarks for Adsorption on Transition Metal Oxide Surfaces: A Comparison of DFT to Experimental Data

Density functional theory (DFT) is commonly used to investigate adsorption and reaction processes on surfaces. While it is widely used, the applicability of DFT to highly correlated transition metal oxide systems with unpaired d-electrons is problematic, especially when using plane wave basis sets. A primary issue is the lack of quality experimental data for adsorbate and reaction systems on well-defined (single crystal) transition metal oxide surfaces to provide benchmarks for the applicability of current DFT methods and the future development of new methods. We have established experimental benchmarks using temperature programmed desorption (TPD) for the heat of adsorption of carbon monoxide on MnO(100) for comparison to DFT simulations on terraces and step defects, using Perdew-Burke-Ernzerhof (PBE) functionals along with DFT+U, DFT-D2, and DFT-D3 packages. Ongoing experimental work with MnO(100) will also provide experimental heat of adsorption data for CO₂ and H₂O on this high spin 3d⁵ transition metal oxide surfaces.