The interdependence of defects, electronic structure and surface chemistry

Abstract

In this article we present three diverse applications of first-principles simulations to problems of materials chemistry and chemical physics. Their common characteristic is that they are essentially problems of the relationships among atomic structures and the properties they promote in real materials and real applications. The studies are on transition-metal oxide surface chemistry, the reactivity and electronic structure of sp(2)-bonded carbon systems, and defects and electrochromic properties in WO(3). In these demanding applications we must have concern for how realistic our model systems are and how well current implementations of DFT perform, and we comment on both.

First-principles study of metal adatom adsorption on graphene

“…Our calculations for binding energy and geometry are in reasonable agreement with previous calculations for Ti and Fe on graphene. [39][40][41] In contrast to the strong binding we observe in our calculations, some experiments suggest that the Tigraphene interaction is weak. 42 This difference may be due to a larger Ti surface density in experiment than in our calculations, which may reduce the Ti-surface interaction.…”

“…47 The hybridization, charge transfer, and magnetic moment are in reasonable agreement with previous calculations. 39 As for Ti, the PDOS for Fe on the H site ͑Fig. 7͒ shows that there is covalent bonding and hybridization between 3d states and graphene states.…”

A Study of the Influence of Composition on the Microstructural Properties of ZnO/Al2O3 Mixed Oxides

“…In order to control the functional properties of materials it is necessary to govern not only their composition and morphology but also their defect structure 15–18. To understand and ultimately control the defect content of inorganic nanostructures can be seen as an important goal.…”

Electronic structure of defects in Sr2MgSi2O7:Eu2+,La3+ persistent luminescence material

“…Both isolated defect species [6][7][8][9][10][11][12][13][14][15][16][17][18][19] and defect aggregates [20][21][22] have been studied in simple oxide materials (e.g. CaO, MgO and TiO 2 ) with density functional theory (DFT) calculations.…”