DFT investigations on the influence of stacking on the electronic structure, absorption, and non-linear optical properties of 3,5-bis[4-(4-methylphenylcarbonyloxy)phenyl]-1,2,4-oxadiazole.

Context: 1,2,4-Oxadiazole serves as a fundamental building block driving advancements across diverse scientific and technological arenas, contributing to the creation of innovative materials for various applications including devices, sensors, medications, agrochemicals, and biomedical instruments. Employing density functional theory (DFT) methods, we investigate the impact of different conformers of an oxadiazole substituted derivative, specifically 3,5-bis[4-(4-methylphenylcarbonyloxy)phenyl]-1,2,4-oxadiazole, in both monomeric and stacked configurations (dimeric and tetrameric). We analyze the electronic structures of various conformers, including assessment of HOMO-LUMO energy gaps, to detect the influence of diverse substituents and stacking arrangements.

Spectroscopic and theoretical investigation on the origin of color in jarosites.

This work aims to understand the origin of the electronic spectra of Fe (d), Cr (d), and V (d) containing jarosites. The electronic spectrum of the Fe-jarosite is currently assigned to spin forbidden transitions. This work shows that the spectra essentially arise due to the tetragonal distortion of the coordination symmetry of the Fe ion in the jarosite crystal, and thereby obviates the need for invoking spin forbidden transitions.

Electronic transitions in layered hydroxides: Consequences of trigonal distortion of octahedral symmetry.

This work describes the assignment of the electronic spectra of metal ions in D coordination symmetry. Layered hydroxides are a class of materials that host transition metal ions such as Ni, Co, and Cr in D coordination symmetry. The electronic spectra of these ions in the layered hydroxides exhibit significant fine structure which is assigned to transitions arising from D coordination symmetry.