Accession Number : ADA134325

Title :   Electronic Spectra from Molecular Dynamics: A Simple Approach.

Descriptive Note : Technical rept.,


Personal Author(s) : Bergsma,John P ; Berens,Peter H ; Wilson,Kent R ; Fredkin,Donald R ; Heller,Eric J

PDF Url : ADA134325

Report Date : Oct 1983

Pagination or Media Count : 20

Abstract : A method is illustrated for computing the contours of electronic absorption bands from classical equilibrium or nonequilibrium molecular dynamics (or equally for equilibrium systems from Monte Carlo or explicit integration over coordinates). The inputs to the calculations are the potential energy curves for the different electronic states and the electronic transition dipole moments between the states as functions of nuclear coordinates. A simple quantum correction by temperature scaling is demonstrated for the thermal equilibrium case. A test is carried out for the I2 visible absorption spectrum involving transitions from the ground X 0+ sub G(1 sigma) to the excited A 1 sub u(3 Pi) 0+ sub u (3 Pi) and B u (II) states, for thermal equilibrium gas phase I2. The electronic band contours are computed and shown to be remarkably similar to the measured contours.

Descriptors :   *Molecules, *Electronic states, *Absorption spectra, Dynamics, Molecular properties, Band spectra, Electron transitions, Dipole moments, Monte Carlo method, Quantum electronics

Subject Categories : Atomic and Molecular Physics and Spectroscopy
      Quantum Theory and Relativity

Distribution Statement : APPROVED FOR PUBLIC RELEASE