Showing papers by "Jonathan Tennyson published in 1983"
TL;DR: In this paper, a hamiltonian is derived for describing the nuclear motions in van der Waals complexes and other non-rigid systems comprising two polyatomic fragments, A and B. This hamiltonians can still be partitioned in the form HA + HB + HINT, just as the space-fixed hamiltoni.
Abstract: We combine earlier treatments for the embedding of body-fixed coordinates in linear molecules with the close-coupling formalism developed for atomdiatom scattering and derive a hamiltonian which is most convenient for describing the nuclear motions in van der Waals complexes and other non-rigid systems comprising two polyatomic fragments, A and B. This hamiltonian can still be partitioned in the form HA + HB + HINT , just as the space-fixed hamiltonian. The body-fixed form, however, has several advantages. We discuss solution strategies for the rovibrational problem in non-rigid dimers, based on this partitioning of the hamiltonian. Finally, in view of the size of the general polyatomic-polyatomic case, we suggest problems which should be currently practicable.
188 citations
TL;DR: In this paper, the vibrational properties of CH 2 + radical were analyzed using a method recently developed for atom-diatom systems, and it was shown that the Coriolis interaction plays a significant role and two alternative embeddings were discussed.
93 citations
TL;DR: In this paper, a variationally exact method of obtaining the rovibrational levels of triatomic potentials is presented, which derives from the close coupling approach in body-fixed coordinates, but uses optimized Morse oscillator functions to give radial basis sets for both the diatomic and complex stretching coordinates.
Abstract: A variationally exact method of obtaining the rovibrational levels of triatomic potentials is presented. This LC‐RAMP method derives from the close‐coupling approach in body‐fixed coordinates, but uses optimized Morse oscillator functions to give radial basis sets for both the diatomic and complex stretching coordinates. The method is suited to the nuclear dynamics of nonrigid molecules and atom–diatom van der Waals complexes. A recent full interaction surface for HeHF is fitted and used for dynamical calculations. The binding energy of the complex increases slowly with HF vibrational excitation. Correlation between the HF and complex vibrational modes is found to be negligible.
78 citations
TL;DR: Rovibrational calculations are performed on an ab initio potential energy surface for lithium cyanide in this paper, and states localized about both the isocyanide structure and the metastable cyanide structure are found.
35 citations
15 Apr 1983
TL;DR: In this paper, the anisotropy of the van der Waals interaction potential was found to strongly perturb the O 2 fine-structure spectrum, suggesting that O 2 Ar finestructure spectra can give detailed information about the Van der Waal interaction potential.
Abstract: Ro-vibrational calculations are performed on O 2 Ar explicitly including coupling to the O 2 electronic spin. Two different empirical potentials are used and give similar fine-structure spectra. The anisotropy in the potential is found to strongly perturb the O 2 fine-structure spectrum suggesting that the O 2 Ar fine-structure spectrum can give detailed information about the anisotropy of the van der Waals interaction potential. Transition strengths for the complex fine-structure transitions are calculated and found to vary by two orders of magnitude. The Zeeman splitting of the levels by interaction with a weak magnetic field is also calculated.
24 citations
TL;DR: In this article, the Van der Waals molecule and the ordered a and y phases of solid N2 have been calculated starting from the same ab initio Nz-Nz potential.
Abstract: The quantum dynamical behavior of the Van der Waals molecule (N& and that of the ordered a and y phases of solid N2 have recently been calculated, starting from the same ab initio Nz-Nz potential. By interpreting the results of these calculations we try to improve our understanding of the librationlinternal rotation motions of the N2 monomers and the orientational order-disorder (a-p) phase transition. Some new results are presented and further (mean-field and libron-model) calculations are proposed which assess explicitly the intermolecular pair correlation effects caused by the anisotropic interaction potential.
6 citations
Journal Article•
TL;DR: In this article, the Van der Waals molecule and the ordered a and y phases of solid N2 have been calculated starting from the same ab initio Nz-Nz potential.
Abstract: The quantum dynamical behavior of the Van der Waals molecule (N& and that of the ordered a and y phases of solid N2 have recently been calculated, starting from the same ab initio Nz-Nz potential. By interpreting the results of these calculations we try to improve our understanding of the librationlinternal rotation motions of the N2 monomers and the orientational order-disorder (a-p) phase transition. Some new results are presented and further (mean-field and libron-model) calculations are proposed which assess explicitly the intermolecular pair correlation effects caused by the anisotropic interaction potential.