Effects of Atomic Scale Roughness at Metal/insulator Interfaces on Metal Work Function
We evaluate the performance of different van der Waals (vdW) corrected density functional theory (DFT) methods in predicting the structure of perfect interfaces between the LiF(001), MgO(001), NiO(001) films on the Ag(001) surface and the resulting work function shift of Ag(001). The results demonstrate that including the van der Waals interaction is important for obtaining accurate interface structures and the metal work function shift. The work function shift results from a subtle interplay of several effects strongly affected by even small changes in the interface geometry. This makes the accuracy of theoretical methods insufficient for predicting the shift values better than within 0.2 eV. Most of the existing van der Waals corrected functionals are not particularly suited for studying metal/insulator interfaces. The lack of accurate experimental data on the interface geometries and surface rumpling of insulators hampers the calibration of existing and novel density functionals.
- Research Organization:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-76RL01830
- OSTI ID:
- 1108134
- Journal Information:
- Physical Chemistry Chemical Physics. PCCP, 15(45):19615-19624, Journal Name: Physical Chemistry Chemical Physics. PCCP, 15(45):19615-19624
- Country of Publication:
- United States
- Language:
- English
Similar Records
Performance of van der Waals Corrected Functionals for Guest Adsorption in the M2 (dobdc) Metal–Organic Frameworks
On the role of long range interactions for the adsorption of sexithiophene on Ag(110) surface