title: One Million Quantum States of Benzene.
abstract: In this study, we compute all of the dynamically relevant vibrational quantum states of benzene, using an "exact" quantum dynamics (EQD) methodology. Benzene (C6H6), in addition to being a very large molecule for EQD (12 atoms, 30 vibrational modes), also has a very large number of vibrational states-around 10(6) in all, lying within 6500 cm(-1) of the ground state. The EQD methodology developed here uses a phase space picture to optimize the truncation of a harmonic oscillator basis-not only with respect to the molecular system of interest but also with respect to the targeted spectral range. By employing several such EQD calculations, targeted to different spectral ranges, a "hybridized" data set is constructed that provides the most accurate results everywhere. In particular, more than 500,000 states are converged to 15 cm(-1) or better.
authors.affiliation: Department of Chemistry and Biochemistry, and Department of Physics, Texas Tech University , P.O. Box 41061, Lubbock, Texas 79409-1061, United States.
authors.forename: Thomas
authors.initials: T
authors.lastname: Halverson
authors.affiliation: Department of Chemistry and Biochemistry, and Department of Physics, Texas Tech University , P.O. Box 41061, Lubbock, Texas 79409-1061, United States.
authors.forename: Bill
authors.initials: B
authors.lastname: Poirier