0000000000075730
AUTHOR
C. Lavín
Low-lying Rydberg states of HCl.
Vertical excitation energies belonging to some different Rydberg series of hydrogen chloride have been determined with a coupled-cluster theoretical approach. These excitation energies have allowed us to calculate electric dipole transition intensities in HCl and allow additional assessment of the calculation approach presently used to provide an adequate description of the valence and Rydberg states of HCl. The molecular quantum defect orbital has been applied to the calculation of oscillator strengths. In particular, new insight is given on the assignment of states as the R1Pi, the 1Delta(4dpi and 5ppi), the 1Sigma+(4dpi), and the nddelta(1Pi, 1Phi) and 4f states.
MQDO theoretical study of the C1Π–X1Σ+ band system of HCl
Abstract Oscillator strengths for P, Q and R rotational lines belonging to the (0, v ″ = 0, 1) and (1, v ″ = 0, 1) bands for the C 1 Π–X 1 Σ + system of HCl have been theoretically studied. The calculations have been performed by following the molecular quantum defect orbital methodology, which has earlier proved to yield accurate intensities for transitions involving Rydberg states in a variety of molecular species. The results appear to be in good accord with the available experimental values. Predictions of a number of unknown intensities have also been made. We expect that the present data might be of help in the interpretation of future experimental measurements.
A theoretical study of the rotational structure of the ϵ(0,0) band of NO
This study has been focused on the ϵ(0,0) band of the nitric oxide molecule, associated with the absorption electronic transition D2Σ+X 2Π, in the energetic vacuum ultraviolet region. A temperature of 295 K has been considered. The Molecular Quantum Defect Orbital (MQDO) methodology, with which reliable spectroscopic data have been reached in the γ(0,0), δ(0,0), and δ(1,0) bands of the same molecule, has also been used for these calculations. We hope that the present results might be of straightforward use in atmospheric and interstellar chemistry. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Rydberg, valence and mixed states in the vertical spectrum of HF
Abstract Size-consistent self-consistent multireference singles and doubles configuration interaction (SC)2–MR–SDCI, and linear response coupled cluster of singles and doubles including triples LR–CCSDR(3) methods, with a basis set of ANO’s augmented with a single series of molecular Rydberg functions, have been applied to the calculation of vertical excitation energies of HF in the 10–16 eV region. Special care has been put in the description of the valence, Rydberg and mixed states. Some advantage has been taken from the different physical contents of the methods to discuss some assignments. The (4,5) f Rydberg states of HF are predicted at 15.2 and 15.5 eV.
Theoretical study of the discrete and continuum spectrum of BeH
The transition intensities supplied in this Letter are directly connected with a description of the discrete and continuum spectrum of BeH. An attempt to meet our goal requires the calculation of the absorption oscillator strengths of several transitions to Rydberg states of BeH, together with differential oscillator strengths which give rise to different dipole-allowed photoionization channels from the molecular ground state. The calculations have been performed with the molecular-adapted quantum defect orbital (MQDO) approach. Predictions of new spectroscopic data on BeH at energies where high Rydberg transitions can take place, including the continuum region of the spectrum have been mad…