Date of Award


Degree Name

Master of Science




Dino Villagrán


The following study is presented in two sections. In the first section variable-temperature magnetic and structural data of two pairs of diruthenium isomers (having an idealized D4h symmetry), one pair having axial ligands and the formula Ru2(DArF)4Cl (where DArF is the anion of a diarylformamidine isomer, and Ar = p-anisyl or m-anisyl) and the other one being essentially identical but devoid of axial ligands and having the formula [Ru2(DArF)4]BF4, show that the axial ligands have a significant effect on the electronic structure of the diruthenium core. Variable-temperature crystallographic and magnetic data as well as density functional theory (DFT) calculations unequivocally demonstrate the occurrence of Ï? interactions between the p orbitals of the chlorine ligand and the Ï?* orbitals in the Ru25+ cores. Electron paramagnetic resonance data show unambiguously that the unpaired electrons are in metal-based molecular orbitals.

On the second section a triple bonded compound W2(TPG)2Cl4, with a D2h symmetry at the core (where TPG is the anion of N,Nâ??,Nâ??- triphenylguanidine), was synthesized and structurally characterized by single-crystal x-ray crystallography, FT-IR, NMR and Raman spectroscopies, and electrochemical methods. The Wâ??W distance in the solid state is 2.2612(4) Ã?, and the compound shows two one-electron reversible reductions at (E1/2) â??0.73, and â??1.04 V (vs Fc/Fc+). A one-electron reduction of the compound resulted in a complex with a bond order of 3.5, which was characterized by Raman and EPR spectroscopies (g = 1.83). The Raman shift of the Wâ??W bond of both complexes are, 290, and 315 cmâ??1, respectively, consistent to the increase in bond order. DFT calculations were performed to aid in the assignment of the Raman shifts, and to help understand their electronic properties.




Received from ProQuest

File Size

59 pages

File Format


Rights Holder

Karen Ventura

Included in

Chemistry Commons