Hamiltonian of theV15Spin System from First-Principles Density-Functional Calculations

Tight-binding Hamiltonian from first-principles calculations

The tight-binding method attempts to represent the electronic structure of condensed matter using a minimal atomic-orbital like basis set. To compute tight-binding overlap and Hamiltonian matrices directly from first-principles calculations is a subject of continuous interest. Usually, first-principles calculations are done using a large basis set or long-ranged basis set (e.g. muffin-tin orbit...

van der Waals bonding in layered compounds from advanced density-functional first-principles calculations.

Although the precise microscopic knowledge of van der Waals interactions is crucial for understanding bonding in weakly bonded layered compounds, very little quantitative information on the strength of interlayer interaction in these materials is available, either from experiments or simulations. Here, using many-body perturbation and advanced density-functional theory techniques, we calculate ...

Magnetism of Chromia from First-Principles Calculations

Role of van der Waals bonding in the layered oxide V2O5: First-principles density-functional calculations

Sparse matter is characterized by regions with low electron density and its understanding calls for methods to accurately calculate both the van der Waals vdW interactions and other bonding. Here we present a first-principles density-functional theory DFT study of a layered oxide V2O5 bulk structure which shows charge voids in between the layers and we highlight the role of the vdW forces in bu...

Ammonia synthesis from first-principles calculations.

The rate of ammonia synthesis over a nanoparticle ruthenium catalyst can be calculated directly on the basis of a quantum chemical treatment of the problem using density functional theory. We compared the results to measured rates over a ruthenium catalyst supported on magnesium aluminum spinel. When the size distribution of ruthenium particles measured by transmission electron microscopy was u...