Depicting electronic distributions from accurate computational first principles: On the relationship between the complex patterns of bonding interaction and the back‐donation phenomenon

Abstract

International audienc

Donor‐acceptor interactions: Transition metal carbonyl group ligand [TM(CO)6]qcomplexes. A case study at correlated level from the topological density point of view

“…Other alternative orbital approaches based on the ideas of quantum information theory particularly those of multiorbital correlations reports similar results than those reported in Ref. .…”

“…In most of the transition metal complexes interaction with several types of π unsaturated ligands like alkenes and alkynes this concept largely holds. However, it may be noted that the terms donation and/or back‐donation does not mean a charge‐transfer in steps, it really is an overall reorganization of electronic charge distribution including all physical effects within the systems resulting in a net charge transfer. …”

“…They have been studied both experimentally and theoretically from the orbital localization framework of the DAHF within the QTAIM and also including an energetic picture analysis within the IQA theory representing a case study to describe their structure by means of the aforementioned charge transfer process . Nevertheless, some details of crucial importance for these systems are not fully realized, as for instance, the two‐ or four‐electron three‐center complex patterns of bonding (2e‐3c, 4e‐3c) and their relationships with this transference process . As it has been mentioned above, the nature of the interaction has been primarily considered as electrostatic in nature, but nonetheless theoretical studies have been performed analyzing the MOs overlap paying special attention to the process of donation through the charge transfer semiempirical Dewar‐Chatt‐Duncanson model which revel a different charge transfer than the naive electrostatic one .…”

“…However, this explanation is limited to one Slater determinant state functions like Hartree‐Fock or Kohn‐Sham Density Functional Theory (DFT) models and cannot be extended explicitly to correlated methods, as for instance, one‐particle reduced density matrix DFT (1‐RDM DFT), Configuration interaction (CI), coupled cluster (CC), or multiconfigurational state functions in which the MO view is lost . To overcome this difficulty as it has been previously shown, our starting point is the electronic density ρ which possesses the whole information of a molecular system and thus it permits its application to any type of state function beyond the one Slater determinant types. Other alternative orbital approaches based on the ideas of quantum information theory particularly those of multiorbital correlations reports similar results than those reported in Ref.…”

“…This topological methodology, applied to different types of electron distribution leads to identify and classify the bonding interactions regarding the determination of localization and type of cp s and the electronic populations in the domains . This methodology exposed above has been successfully applied to classical as well as complex molecular structures ranging for instance, from electron deficient compounds like boron hydrides, closoboranes, molecular organic ions, simple organo‐metallic systems, metalloid clusters, and simple one‐ligand one‐metal systems …”