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In this work, surface-enhanced vibrational spectroscopy and normal vibrational spectroscopy as well as density functional theory (DFT) computational methods have been employed to investigate the nature of the chemical adsorption and orientation of the surface species generated from salicylic acid at silver surfaces. The structure of salicylic acid and its IR and Raman spectra are determined at the B3LYP/6-31l+G(d,p) level of theory. These results are used in the assignment of the vibrational spectra. Surface-enhanced Raman scattering (SERS) spectra obtained from silver island films thinly coated with salicylic acid confirm chemical adsorption on the Ag nanostructures. To probe the nature of this surface complex, the optimized geometries and IR and Raman spectra of two model salicylate-silver complexes (Ag1 and Ag2) were calculated at the B3LYP/Lan12DZ level of theory. It was found that good agreement exists between experimentally observed SERS spectra and the simulated SERS spectra of a complex with the salicylate monoanion bound to a [Ag.sup.+] ion through its carboxylate group (Ag1). The carboxylate silver salt of salicylic acid (essentially the Ag1 complex) was also prepared, and its IR and Raman spectra were recorded for comparison with the surface-enhanced vibrational spectra. These results, along with the application of surface selection rules, suggest that salicylic acid is deprotonated at silver surfaces, interacting through its carboxylate group a|one, and is preferentially in a tilted head-on orientation. Key words: chemisorption, salicylic acid, silver, density functional theory, surface-enhanced Raman scattering, reflection-absorption IR spectroscopy, surface-enhanced IR absorption.

Full account of the total synthesis and absolute stereo chemical assignment of (+)-torreyanic acid is reported. Thermolysis experiments are conducted on a model dimer based on the torreyanic acid core structure and facile retro Diels-Alder reaction processes and equilibration of diastereomeric 2H- pyrans is observed.

Salicylic anion abstraction and effusion are analyzed in different solvents and solvent mixtures. The significant Stokes shift observed for this anion is considered to indicate a rapid excited phase proton transfer reaction to its keto form.

The total synthesis of both enantiomers of salicylihalamide A, a revision of the absolute configuration assigned to the natural product, and extensive structure-function studies with synthetic salicylihalamide variants are reported. The advantage of a flexible synthetic strategy was highlighted by quickly advance the ring-closing olefin metathesis approach as the method of choice to build the 12-membered benzolactone core of salicylihalamides.

Salicylic and phthalic acids are used to study the complexation of aromatic carboxylic acids with Al(III) in solution and on mineral surfaces. A method for studying aqueous and surface carboxylic acids/metal complexes with UV Raman is developed.

The multidimensional wave packet dynamics of salicylaldimine following ultrafast infrared laser excitation of the OH-bending and stretching vibrations is discussed. Coherent wave packet dynamics is observed after excitation of OH-bending fundamental transition. Strong anharmonic mode couplings to the stretching transition cause intramolecular vibrational energy redistribution on a time scale of about 700 fs.