Electronic Structure of Three Center Two Electron Bonds in Boron Rich Materials: A Study of Molecules, Crystals, and Amorphous Solids using the ab initio Orthogonalized Linear Combination of Atomic Orbitals Method
Date
2020Metadata
[+] Show full item recordAbstract
It has been shown that isomers of carborane, α and β rhombohedral boron, α and β tetragonal boron, γ boron, and boron carbide tend to form icosahedral structures. If the icosahedra were formed with pure boron, it has been demonstrated that there is an insufficient number of electrons to populate all the molecular orbitals that would nominally be required for molecular cohesion. To overcome that electron deficiency, the icosahedral boron units tend to form interesting bonding structures with their neighbors in solids, and/or for molecular boron the icosahedra tends to incorporate substitutional carbon atoms. The resultant bonding structures are often of a 3 center 2 electron nature. The visualization of these 3 center 2 electron bonds varies in the literature and this exposes a discontinuity with how multi-center bonds should be perceived. Here, I have attempted to reconcile these delocalized bonds with the common “ball-and-stick” molecular model using an extension to Mulliken Population Analysis within the Orthogonalized Linear Combination of Atomic Orbitals method.
Table of Contents
Introduction -- Methods -- Results and discussion -- Conclusions and future work --Appendix. Created and altered scripts and programs
Degree
M.S. (Master of Science)