Ti-doped nano MgAl2O4 for white emission was synthesized by combustion method. Extrinsic Schottky defects, Al vacancies and Ti4+ dopant in Al sites, which are considered to be responsible for bluish-white emission, were observed by STEM on the surface of Ti-doped nano MgAl2O4 powder. The stabilities of the Schottky defect associates, (TiAl·-VAl''')'', were demonstrated by DFT calculation. The e...

In this study, mitoxantrone and its halogenated derivatives have been designed by density functional theory (DFT) to explore their structural and thermodynamical properties. The performance of these drugs was also evaluated to inhibit DNA topoisomerase type IIα (TOP2A) by molecular docking calculation. Noncovalent interactions play significant role in improving the performance of halogenated dr...

The lack of accurate transferable local pseudopotentials represents one of the remaining barriers to the general application of orbital-free density functional theory ~OF-DFT, a linear scaling technique!. Here we report a method to generate high quality ab initio local pseudopotentials ~LPS’s! for use in condensed matter DFT calculations. We exploit the first Hohenberg-Kohn theorem, which state...

The exchange-correlation functional is the key object in the understanding and application of density functional theory (DFT). Development of approximations to the exact functional is extremely challenging, as it aims to give a universal functional that works for all densities. To shed light on this issue in any manner is of great importance, and exact conditions offer a possible path forward. ...

Density Functional Theory is situated within the evolution of Quantum Chemistry as a facilitator of computations and a provider of new, chemical insights. The importance of the latter branch of DFT, conceptual DFT is highlighted following Parr's dictum "to calculate a molecule is not to understand it". An overview is given of the most important reactivity descriptors and the principles they are...

Analytic second derivatives of the energy with respect to nuclear coordinates have been developed for spin restricted density functional theory (DFT) based on the fragment molecular orbital method (FMO). The derivations were carried out for the three-body expansion (FMO3), and the two-body expressions can be obtained by neglecting the three-body corrections. Also, the restricted Hartree-Fock (R...

Ammonia (NH3) nitridation on an Fe surface was studied by combining density functional theory (DFT) and kinetic Monte Carlo (kMC) calculations. A DFT calculation was performed to obtain the energy barriers (Eb) of the relevant elementary processes. The full mechanism of the exact reaction path was divided into five steps (adsorption, dissociation, surface migration, penetration, and diffusion) ...