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Molecular diatomic spectroscopy data

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 Added by Laura McKemmish K
 Publication date 2021
  fields Physics
and research's language is English




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Accurate and comprehensive diatomic molecular spectroscopic data have long been vital in a wide variety of applications for measuring and monitoring astrophysical, industrial and other gaseous environments. These data are also used extensively for benchmarking quantum chemistry and applications from quantum computers, ultracold chemistry and the search for physics beyond the standard model. Useful data can be highly detailed like line lists or summative like molecular constants, and obtained from theory, experiment or a combination. There are plentiful (though not yet sufficient) data available, but these data are often scattered. For example, molecular constants have not been compiled since 1979 despite the existing compilation still being cited more than 200 times annually. Further, the data are interconnected but updates in one type of data are not yet routinely applied to update interconnected data: in particular, new experimental and ab-initio data are not routinely unified with other data on the molecule. This paper provide information and strategies to strengthen the connection between data producers (e.g. ab-initio electronic structure theorists and experimental spectroscopists), data modellers (e.g. line list creators and others who connect data on one aspect of the molecule to the full energetic and spectroscopic description) and data users (astronomers, chemical physicists etc). All major data types are described including their source, use, compilation and interconnectivity. Explicit advice is provided for theoretical and experimental data producers, data modellers and data users to facilitate optimal use of new data with appropriate attribution.



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177 - A. Hashemloo , C. M. Dion 2015
We present models for a heteronuclear diatomic molecular ion in a linear Paul trap in a rigid-rotor approximation, one purely classical, the other where the center-of-mass motion is treated classically while rotational motion is quantized. We study the rotational dynamics and their influence on the motion of the center-of-mass, in the presence of the coupling between the permanent dipole moment of the ion and the trapping electric field. We show that the presence of the permanent dipole moment affects the trajectory of the ion, and that it departs from the Mathieu equation solution found for atomic ions. For the case of quantum rotations, we also evidence the effect of the above-mentioned coupling on the rotational states of the ion.
201 - Xiangyue Liu , Gerard Meijer , 2020
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152 - Amelie Ferre 2014
Strong field transient grating spectroscopy has shown to be a very versatile tool in time-resolved molecular spectroscopy. Here we use this technique to investigate the high-order harmonic generation from SF6 molecules vibrationally excited by impulsive stimulated Raman scattering. Transient grating spectroscopy enables us to reveal clear modulations of the harmonic emission. This heterodyne detection shows that the harmonic emission generated between 14 to 26 eV is mainly sensitive to two among the three active Raman modes in SF6, i.e. the strongest and fully symmetric nu 1-A1g mode (774 cm-1, 43 fs) and the slowest mode nu5-T2g (524 cm-1, 63 fs). A time-frequency analysis of the harmonic emission reveals additional dynamics: the strength and central frequency of the nu 1 mode oscillate with a frequency of 52 cm-1 (640 fs). This could be a signature of the vibration of dimers in the generating medium. Harmonic 11 shows a remarkable behavior, oscillating in opposite phase, both on the fast (774 cm-1) and slow (52 cm-1) timescales, which indicates a strong modulation of the recombination matrix element as a function of the nuclear geometry. These results demonstrate that the high sensitivity of high-order harmonic generation to molecularvibrations, associated to the high sensitivity of transient grating spectroscopy, make their combination a unique tool to probe vibrational dynamics.
71 - Xiangyue Liu , Gerard Meijer , 2020
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