Related Experiment Video
Updated: Jan 24, 2026
06:56
Generating a Fractal Microstructure of Laminin-111 to Signal to Cells
Published on: September 28, 2020
1.3K
Specific Reaction Parameter Density Functional Based on the Meta-Generalized Gradient Approximation: Application to
Egidius W F Smeets1, Johannes Voss2, Geert-Jan Kroes1
1Leiden Institute of Chemistry, Gorlaeus Laboratories , Leiden University , P.O. Box 9502, 2300 RA Leiden , The Netherlands.
The Journal of Physical Chemistry. A
|June 1, 2019
Summary
New meta-generalized gradient approximation (meta-GGA) functionals accurately describe hydrogen dissociation on copper and silver surfaces, improving metal descriptions. These functionals offer a more precise understanding of molecule-metal interactions in catalysis and surface science.
Area of Science:
- Computational Chemistry
- Surface Science
- Materials Science
Background:
- Specific reaction parameter density functionals (SRP-DFs) accurately model dissociative chemisorption on metals.
- Existing SRP-DFs, based on generalized gradient approximation (GGA) functionals, provide accurate molecule-metal interactions but poor metal descriptions.
- A need exists for improved functionals that balance surface interaction accuracy with better bulk metal properties.
Purpose of the Study:
- To develop and evaluate new meta-GGA based SRP-DFs for hydrogen dissociation on metal surfaces.
- To assess the performance of these new functionals in describing both molecule-metal interactions and bulk metal properties.
- To compare the accuracy of meta-GGA SRP-DFs against existing GGA-based functionals.
Main Methods:
- Introduction of three new meta-GGA functionals (MS-PBEl, MS-B86bl, MS-RPBEl) based on the 'made-simple' (MS) concept.
- Calculation of potential energy surfaces (PESs) using these new functionals.
- Quasi-classical trajectory (QCT) calculations to simulate H2 and D2 dissociation/desorption experiments on Cu(111) and Ag(111) surfaces.
Main Results:
- The new MS meta-GGA functionals accurately reproduce experimental results for H2 dissociation on Cu(111) within chemical accuracy.
- These functionals also show improved accuracy for H2/D2 interactions with Ag(111) compared to previous SRP-DFs.
- The MS functionals provide significantly better descriptions of Cu, Ag, Au, and Pt metals than the standard PBE functional.
Conclusions:
- Meta-GGA functionals can be successfully developed as SRP-DFs, overcoming limitations of GGA-based approaches.
- The new MS functionals offer a superior balance of accuracy for both surface reactions and bulk metal properties.
- While highly accurate, the tunability of reaction barrier heights with these MS functionals is limited, impacting their application for certain systems like H2 + Ag(111).
Related Concept Videos
01:29Application of Linearization and Approximation
83
A drone flying through complex terrain often relies on more than one sensing method to estimate small changes in altitude. Along with direct measurements, air pressure provides a useful indirect indicator of vertical movement. Atmospheric pressure decreases as altitude increases, and this relationship is commonly described using an exponential model. Although accurate, converting pressure measurements into altitude values requires calculations that are too complex to perform repeatedly during...
83
01:28Acid Suppressive Drugs for Peptic Ulcer Disease: Histamine H2-Receptor Antagonists
965
Histamine H2 receptors, which are intricately located on the basolateral membrane of parietal cells, play a crucial role in modulating gastric acid secretion. When released from enterochromaffin-like cells, histamine engages H2 receptors, initiating the cyclic AMP (cAMP) pathway. In this pathway, adenylyl cyclase converts ATP into cAMP, elevating intracellular cAMP levels. The activation of protein kinase A follows, stimulating the proton pump. This stimulation prompts the secretion of hydrogen...
965
03:43Applications of the Ideal Gas Law: Molar Mass, Density, and Volume
63.3K
The volume occupied by one mole of a substance is its molar volume. The ideal gas law, PV = nRT, suggests that the volume of a given quantity of gas and the number of moles in a given volume of gas vary with changes in pressure and temperature. At standard temperature and pressure, or STP (273.15 K and 1 atm), one mole of an ideal gas (regardless of its identity) has a volume of about 22.4 L — this is referred to as the standard molar volume.
63.3K
01:26What is an Electrochemical Gradient?
127.5K
Adenosine triphosphate, or ATP, is considered the primary energy source in cells. However, energy can also be stored in the electrochemical gradient of an ion across the plasma membrane, which is determined by two factors: its chemical and electrical gradients.
The chemical gradient relies on differences in the abundance of a substance on the outside versus the inside of a cell and flows from areas of high to low ion concentration. In contrast, the electrical gradient revolves around an...
The chemical gradient relies on differences in the abundance of a substance on the outside versus the inside of a cell and flows from areas of high to low ion concentration. In contrast, the electrical gradient revolves around an...
127.5K
01:27Density, Specific Weight, Specific Gravity and Compressibility of Fluid
1.5K
Density, specific weight, specific gravity, and compressibility are fundamental properties of fluids. Density is the mass per unit volume, characterizing the mass of a fluid system. It influences buoyancy, pressure, flow dynamics, viscosity, thermal conductivity, and sound propagation. For instance, in pipeline design, accurate density measurements ensure that the pipeline can handle the fluid's mass.
Specific weight represents the weight per unit volume and is calculated by multiplying...
Specific weight represents the weight per unit volume and is calculated by multiplying...
1.5K
03:26Acids, Bases and Neutralization Reactions
63.6K
An acid-base reaction is one in which a hydrogen ion, H+, is transferred from one chemical species to another. Such reactions are of central importance to numerous natural and technological processes, ranging from the chemical transformations within cells or lakes and oceans to the industrial-scale production of fertilizers, pharmaceuticals, and other substances essential to the society.
63.6K