Accession Number : ADA295429

Title :   Dynamics and Spectra of Highly Excited Molecules.

Descriptive Note : Final technical rept. 1 Nov 91-31 Oct 94,

Corporate Author : OREGON UNIV EUGENE DEPT OF CHEMISTRY

Personal Author(s) : Kellman, Michael E.

PDF Url : ADA295429

Report Date : 28 MAR 1995

Pagination or Media Count : 14

Abstract : Significant progress has been made toward the ultimate goal of a comprehensive framework for systematic analysis of highly excited vibrational states of molecules. Traditional methods are predicated on assignment of eigenstates in terms of quantum numbers, such as the number of quanta in each normal mode, which are physically meaningful only in the low-energy, near-harmonic regime. What is needed is a new or at least much more general framework for spectra complicated by strong interactions among some or all of the degrees of freedom. We have been working toward such a framework through a systematic quest for understanding of the complex semiclassical dynamics underlying the quantum spectrum of the molecule. The main accomplishments achieved under this contract include: (1) determination of spectral patterns associated with phase space bifurcation structure and related spectral assignments with new quantum numbers; (2) assignment of spectra of polyatomics with three or more coupled degrees of freedom, following a bifurcation analysis of a chaotic Hamiltonian obtained from spectroscopic quantum fitting Hamiltonians; (3) the discovery of precessional modes in the bending spectra of acetylene, with assignment and related spectral patterns, following a bifurcation analysis of the spectral fitting Hamiltonian. jg

Descriptors :   *DYNAMICS, *MOLECULES, *EXCITATION, *SPECTRA, COUPLING(INTERACTION), SPECTROSCOPY, QUANTUM THEORY, EIGENVALUES, BENDING, DEGREES OF FREEDOM, ELECTRONIC STATES, PATTERNS, ACETYLENE, BIFURCATION(MATHEMATICS), HAMILTONIAN FUNCTIONS, FITTINGS, VIBRATIONAL SPECTRA.

Subject Categories : Physical Chemistry
      Inorganic Chemistry
      Atomic and Molecular Physics and Spectroscopy
      Quantum Theory and Relativity

Distribution Statement : APPROVED FOR PUBLIC RELEASE