Abstracts

Correlations in Multipole Refinements

The Hansen-Coppens Multipole Model partitions the electron density into three components – core density, spherical valence density and aspherical valence density.

Read More

Defining Tools for Complex Small Molecules to Enable Assessment of Quality and Appropriate Reuse of Data

An important, but often difficult to evaluate, aspect of small molecule crystallographic structure analysis is an understanding of how a refinement has been performed. One of the tools tha can be used is to evaluate the likelihood of a given bond in a structure, and from this calculate the total likelihood of the structure

Read More

Electron-density analysis of halide · · · halide through-space magnetic exchange

We present a combined experimental and density functional theory study that characterizes the charge and spin density in NiX2(3,5-lutidine)4 (X = Cl, Br and I). In this material, magnetic exchange interactions occur via Ni2+–halide … halide–Ni2+ pathways, forming one-dimensional chains.

Read More

Experimental electronic structure of coordination compounds

Thanks to the continuous improvement of single-crystal X-ray diffractometers and data processing software, it is expected that experimental electronic structures are approaching reality. However, we still see certain differences between experimental and theoretical results.

Read More

Hirshfeld Atom Refinement for Spin State Investigations on Transition Metal Complexes

The spin states of transition metal complexes have been extensively studied using both theoretical and analytical methods. Here, we demonstrate an alternative method utilising Hirshfeld Atom Refinement…

Read More

Implementation of density matrix tight-binding (PTB) for quantum crystallographic refinement in NoSpherA2

The computational cost associated with simulations of large … presents a significant challenge to the adoption of quantum crystallographic refinement as a standard refinement tool. A possibility to improve computational time, without sacrificing much accuracy is the use of semiempirical methods, which use empirical parameters..

Read More

Quantum Crystallographic Investigation of Two-Electron Multicentre Bonds in Radical Systems

We present a systematic quantum crystallographic investigation of various 2e/mc-bonded radical systems, ranging from discrete dimers to 2D arrays. The simplest systems studied include TCNE radical anion dimers, while more complex systems feature 2D arrays of TCNQ radical anions with partial charges of −1/2.

Read More

Quantum Crystallography in Materials Science

Selected quantum crystallographic tools will be examined for their ability to elucidate structure–property correlations in a range of functional materials. Building on recent literature and case studies from ongoing research, particular focus will be placed on how charge density analyses have shed light on magnetic, optical, electronic and other properties.

Read More

Similarities and Differences in the Electron Density of Cumulated and Conjugated Systems

QTAIM calculations were conducted to shed light on the nature of bonds in even and odd cumulated systems, with n = 3, 4, 5 and 6, functionalized with alkyls, aryls and N-heterocyclic carbenes (NHCs).

Read More

The agreement between DFT and CASSCF of a Cr(I)-Cr(I) study

The metal-metal interaction fascinated scientist for many years. In this study, the Cr(I)-Cr(I) bond of complex S was studied by both single- and multi-determinant approaches.

Read More
Tags