Volume 111, Issue 14, 08 October 1999
Index of content:
Enhanced orientation of polar molecules by combined electrostatic and nonresonant induced dipole forces111(1999); http://dx.doi.org/10.1063/1.479917View Description Hide Description
Recent experiments have demonstrated the efficacy of orienting low rotational states of a linear polar molecule in a static electric field, or aligning a molecule (polar or not) in an intense nonresonant laser field, We present theoretical results showing that the combined action of and can markedly sharpen orientation, particularly by introducing a pseudo-first-order Stark effect for tunneling doublets created by the polarizability interaction. Also, if and are not collinear, the molecular axis can be localized with respect to φ as well as θ, since M states as well as J states undergo hybridization. Another benefit is a means to eliminate “wrong way orientation” which otherwise occurs for “low-field seeking” states.
111(1999); http://dx.doi.org/10.1063/1.479918View Description Hide Description
The origin and three vibronic bands of the electronic transition of linear have been observed in the gas phase. The carbon chain is produced in a slit nozzle employing both discharge and ablation techniques. Cavity ring down spectroscopy is used to measure the electronic transition. The origin band is found at 510.94(1) nm, shifted 29 to the red of the value in a neon matrix. Intramolecular processes lead to broadening and irregularities in the rotational structure. The relation to astronomical observations is discussed.
111(1999); http://dx.doi.org/10.1063/1.479919View Description Hide Description
An iterative algorithm is presented for evaluating the path integral expression for the reduced density matrix of a quantum system interacting with an anharmonic dissipative bath whose influence functional is obtained via numerical methods. The method allows calculation of the reduced density matrix over very long time periods.