A Chronicle About the Development of Electronic Structure Theories for Transition Metal Complexes

Abstract

We review here the development of electronic structure theories for transition metal complexes from the 1950s to present days. The different methods are compared through applications to permanganate and other tetroxo systems.

Constricted Variational Density Functional Theory Approach to the Description of Excited States

“…Excited states are reached in this scheme by promoting electrons from occupied to virtual ground state levels followed by a KS calculation on the new electron configuration. The ΔSCF approach has met with considerable success for those lower excited states which can be represented by a single orbital replacement (SOR) [39][40][41][42][43][44][45][46][47][48][49]. However, it is plagued by SCF-convergence problems.…”

On the Origins of Some Spectroscopic Properties of “Purple Iron” (the Tetraoxoferrate(VI) Ion) and Its Pourbaix Safe-Space

“…A chronological account of the development of theories on the electronic structures of transition metal complexes from 1950s to 2011, centred on Density Function Theory, Hartree-Fock and post Hartree-Fock methods, was published by the late Professor Tom Ziegler (1945Ziegler ( -2015 of the University of Calgary (Canada) [112]. He compared the methods through their applications to permanganate [Mn (+VII) O 4 ] − and other tetraoxo species.…”

The electronic structure of the aqueous permanganate ion: aqueous-phase energetics and molecular bonding studied using liquid jet photoelectron spectroscopy

“…The RPES results are also used to identify the atomic parentages and confirm hybridizations of a number of the valence molecular orbitals. [39][40][41] Furthermore, intermolecular solute and solvent electronic coupling phenomena are identified through detection of resonant ICD processes following soft X-ray photoexcitation. Our cumulative results are used to construct an aqueous-phase molecular orbital diagram for the MnO 4 À (aq.)…”

“…Existing theoretical calculations highlight the retention of an average tetrahedral anion symmetry in moving from the gas- 54 to the (bulk) aqueous-phase. § Accordingly, a T d point group is utilised along with existing (isolated-molecule) molecular orbital diagrams [54][55][56] to assign and label the MnO 4 À (aq.) PES signals.…”