MO Theory
Hückel Theory I and II JCE
James M. LoBue, Georgia Southern University
These documents provide an introduction to the Heisenberg formulation of quantum mechanics.Huckel I provides an introduction to generating Huckel Theory results along with an introduction to HOMO-LUMO transition energies and the prediction of nucleophilic and electrophilic substitution. Huckel II treatsthe generation of partial charges, bond orders, and the determination of aromatic character. Since these topics have ab-initio analogs, Huckel I and II provide a "hands-on" introduction to important aspects of computational chemistry as well.
Orbital Graphing JCE
Mark David Ellison, Wittenberg University
This document provides three-dimensional graphs of the angular parts of hydrogen-like atomic orbitals. Linear combinations of orbitals result in the familiar px and py orbitals. The process is repeated for some of the d orbitals. The second part of the document shows linear combinations of s and p orbitals to construct hybrid sp, sp2, and sp3 orbitals.
sp3dn Orbital Hybrids and Molecular Geometry JCE
Mark David Ellison, Wittenberg University
A Mathcad document that gives students the opportunity to explore hybrid orbitals that give rise to octahedral, trigonal bipyramidal, square planar, and square pyramidal shapes. LCAO is use to generate the hybrid shapes.
Visualization of Wavefunctions of the Ionized Hydrogen Molecule JCE
John L. Johnson, The Pennsylvania State University
Mathcad and the Shooting Method, are used to solve the Schrodinger equation for the H2+ molecule. The angular portions of the wavefunctions are the spheroidal harmonics, which when plotted show the shapes of molecular orbitals. These exact solutions are compared with those obtained from the LCAO method, using hydrogenic orbitals as basis functions. Plot of the electronic charge densities show the concentration of charge that distinguishes bonding and anti-bonding states. The energies of the wavefunctions as a function of internuclear distance for the eight lowest molecular energy states are calculated.