Bachelor's defense: Ivar Gunnarsson

Title: Valence bond theory and organic molecules

In this talk, I will present a method of studying organic molecules and chemical bonds using methods of Quantum Mechanics. This is done by considering a simple interaction between valence electrons of two atoms and then expanding on the system, introducing the Hubbard model. A Hamiltonian acting on a subspace of the Hilbert space is derived and a picture formalism is developed to make the analysis of the lattices simple. Using this, the ground state of organic compounds are found and the spin density of free radicals are analyzed.