Computational Studies of Transition Metals and Small Molecules
The chemistry that transition metals can access due to their d orbitals has expanded the horizons of many fields in chemistry. The work covered in this dissertation focuses on designing a computer system for performing computational studies, and a wide range of computational chemical studies of transition metals in various applications including predictions of bulk properties, homogenous/heterogenous catalysis, and the acidity of solvated transition metals for use in proteomics. Utilizing high-performance computers allows chemists to explore the d-block elements to aid in the analysis of experimental results or to explore new chemistry cheaply, safely, and ‘greenly’. Although a handful of high-performance computer cluster building recipes are available for general use, a free-open source recipe geared towards computational chemistry with compatibility for a broad range of computer hardware is provided. High level MO theory studies of coinage-metal trimers were done to study their potential energy surfaces. While exploring these potential energy surfaces, a novel, vibrationally bound, local minimum for the gold trimer was discovered, one of the first examples of bond angle isomerism. The normalized clustering energies of small metal clusters (n = 2-20) of the coinage metals were extrapolated to predict the cohesive energy of the bulk metal. The importance of spin orbit coupling for the binding energies of gold clusters was found. Density functional theory was used to calculate the binding energies of organic molecules including cyclohexane and benzene on a model of the rutile TiO2(110) surface, an important first step in heterogeneous catalysis of these species on a transition metal oxide. The calculated vibrational frequencies were used to predict reliable prefactors for analysis of temperature programmed desorption experiments. Mechanisms for the homogenous catalysis of the reduction of CO2 to formate using a triphosphine-ligated Cu(I) catalyst were developed. A mechanism of enhanced protonation involving transition metals in an electrospray ionization source in mass spectrometry for proteomic applications was developed.