The experimental method to be employed by Dr. Dyke will be infrared absorption spectroscopy. Diode lasers will be used to study the spectral region from 350 - 3500 reciprocal cm., utilizing both molecular beams and static gas samples to provide varying degrees of simplicity and information content in the observed spectra. Microwave-infrared double resonance techniques will be used to increase the spectral resolution and to aid in assigning spectra. To access the important spectral region below 350 recoprocal cm., a far infrared Fourier transform spectrometer with high sensitivity detectors will be employed, allowing many of the low frequency intermolecular modes of complexes to be directly examined. Specific systems to be studied include hydrogen-containing dimers and mixed complexes of monomers. Intermolecular forces manifested in hydrogen bonds and van der Waals interactions play an important part in determining the properties of a wide variety of condensed phase and macromolecule systems. Theories of liquid water, aqueous solutions and macromolecule conformations are examples of areas where these interactions are of particular interest. To understand these systems, accurate information concerning intermolecular potential energy surfaces is vital. One way to attack this problem is to form complexes held together by hydrogen bonds or van der Waals interactions, and to study them by various spectroscopic techniques. If enough spectroscopic data is in hand, substantial information about the relevant potential energy surfaces can be gained, and when available, combined with scattering or thermodynamic data to give a more comprehensive view of intermolecular forces and the nature of these weak interactions.
