Topic
Valence (chemistry)
About: Valence (chemistry) is a research topic. Over the lifetime, 24937 publications have been published within this topic receiving 645252 citations. The topic is also known as: valency.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this paper, density functional calculations aimed at identifying the atomistic and electronic structure origin of the valence and conduction band, and band gap tunability of halide perovskites ABX3 upon variations of the monovalent and bivalent cations A and B and the halide anion X were performed.
Abstract: We performed density functional calculations aimed at identifying the atomistic and electronic structure origin of the valence and conduction band, and band gap tunability of halide perovskites ABX3 upon variations of the monovalent and bivalent cations A and B and the halide anion X. We found that the two key ingredients are the overlap between atomic orbitals of the bivalent cation and the halide anion, and the electronic charge on the metal center. In particular, lower gaps are associated with higher negative antibonding overlap of the states at the valence band maximum (VBM), and higher charge on the bivalent cation in the states at the conduction band minimum (CBM). Both VBM orbital overlap and CBM charge on the metal ion can be tuned over a wide range by changes in the chemical nature of A, B and X, as well as by variations of the crystal structure. On the basis of our results, we provide some practical rules to tune the valence band maximum, respectively the conduction band minimum, and thus the band gap in this class of materials.
121 citations
TL;DR: In this article, the electron energy loss spectra of ethane, propane, n-butane and n-pentane were measured under dipole-dominated conditions (2.8 ke V impact energy, small angle).
121 citations
TL;DR: In this article, all-electron contracted double zeta valence plus polarization function (DZP) basis sets for the elements Cs, Ba, La, from Hf to Ir, and from Au to Rn are constructed for using in conjunction with the non-relativistic and Douglas-Kroll-Hess (DKH) Hamiltonians.
121 citations
TL;DR: In this paper, the authors give an overall view of all the five actors that influence the intramolecular electron transfer scenario, as the key for constructing new molecules, enhancing or combining multifunctional properties.
121 citations
TL;DR: In this paper, the analysis of 2p XAS, XMCD and 2p EELS is discussed, including isolated iron atoms, solids and coordination compounds, including binary oxides, perovskites and spinel systems.
121 citations