Lynne L. Haas

Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School



The infrared spectra of triphenylphosphine, triphenylphosphine oxide, and their complexes have been studied by several groups of workers. These spectra are helpful in determining the modes of complex formation and elucidating structural aspects of the complexes. Although many of the bands can be attributed to phenyl modes, the areas between 1200 and 1050 cm-1 and between 800 and 700 cm-1 contain bands which arise from bonding within the ligand (phosphorus-phenyl linkages) or bonding of the ligand to a metal ion (phosphorus-metal linkages in triphenylphosphine complexes and oxygen-metal linkages in triphenylphosphine oxide complexes.) Work with triphenylphosphine at South Dakota State University revealed that bands in the 700 cm-1 and 1100 cm-1 region were often present but had received no definitive assignments in previous spectral studies. Some workers preferred to ignore bands in these regions (particularly those in the 700 cm-1 region) even though they often appear as some of the most intense absorption in the spectra. Most simply tried to make sweeping generalizations of structure or bonding to account for the bands. Preliminary work revealed that these generalizations break down when a broad range of complexes is examined. It was also apparent that the intensity f the bands relative to adjacent bands varied in different types of complexes, and could be related to structure. The aspect of intensity has not been considered by previous studies. Because of the neglect of these aspects of the infrared spectra, this research was undertaken in order to clarify ambiguous assignments ad determine the reasons for differences in the characteristic features of triphenylphosphine, triphenylphosphine oxide and various types of complexes involving these ligands. In addition, a complex obtained from the reaction of triphenylphosphine and indium (III) perchlorate 8-hydrate unexpectedly produced a spectrum quite different from those of other phosphine complexes. This complecation led to an investigation of the adducts obtained from the interaction of hydrogen chloride of hydrogen bromide and triphenylphosphine oxide in order to determine the spectral characteristics of hydrogran bonding in these adducts. This information was use to draw conclusions concerning the type of bonding present in certain complexes of transition metal salts.

Library of Congress Subject Headings

Chemistry, Inorganic

Infrared spectra



Number of Pages



South Dakota State University