Efficient quantum calculations of vibrational states of vinylidene in full dimensionality: A scheme with combination of methods
Document Type
Article
Publication Date
1-1-2008
Abstract
Full-dimensional quantum calculations of vibrational states of C2 H2 and C2 D2 are performed in the high-energy region (above 20 400 cm-1 relative to the acetylene minimum). The theoretical scheme is a combination of several methods. To exploit the full parity and permutation symmetry, the CC-HH diatom-diatom Jacobi coordinates are chosen; phase space optimization in combination with physical considerations is used to obtain an efficient radial discrete variable representation, whereas a basis contraction scheme is applied for angular coordinates. The preconditioned inexact spectral transform method combined with an efficient preconditioner is employed to compute eigenstates within a desired spectral window. The computation is efficient. More definite assignments on vinylidene states than previous studies are acquired using the normal mode projection; in particular, a consistent analysis of the 1 (symmetric CH stretch) state is provided. The computed vinylidene vibrational energy levels are in general good agreement with experiment, and several vinylidene states are reported for the first time. © 2008 American Institute of Physics.
Publication Source (Journal or Book title)
Journal of Chemical Physics
Recommended Citation
Li, B., & Bian, W. (2008). Efficient quantum calculations of vibrational states of vinylidene in full dimensionality: A scheme with combination of methods. Journal of Chemical Physics, 129 (2) https://doi.org/10.1063/1.2953706