High-resolution Spectroscopy Of Mgkr+ In Its Ground And Low-lying Electronically Excited States

Kreis, Carla

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https://hdl.handle.net/2142/116859 Copy

Description

Title

High-resolution Spectroscopy Of Mgkr+ In Its Ground And Low-lying Electronically Excited States

Author(s)

Kreis, Carla

Contributor(s)

• Merkt, Frédéric
• Génévriez, Matthieu

Issue Date

2022-06-22

Keyword(s)

Ions

Abstract

Diatomic molecules RgM consisting of a rare-gas atom Rg and an alkaline-earth-metal atom M and their singly and doubly-charged cations RgM$^+$ and RgM$^{2+}$ have unusual chemical properties that are related to the low first and second ionization energies of M and the high ionization energy of Rg. In MgAr the second ionization energy of Mg is lower than the first ionization energy of Ar. Consequently, MgAr$^{2+}$ is thermodynamically stable and Rydberg series of MgAr$^+$ can be observed that converge on the $\mathrm{X}^{2+} \;^1\Sigma^+$ ground state of MgAr$^{2+}$.\footnote{D. Wehrli, M. G{\'{e}}n{\'{e}}vriez and F. Merkt, Phys. Chem. Chem. Phys., 23, 10978, (2021) and references therein} In this contribution, we present the results of spectroscopic investigations of MgKr$^+$ in its ground and low-lying electronically excited states that complement earlier studies of this cation.\footnote{J. G. Kaup and W. H. Breckenridge, J.Chem. Phys. 107, 2180, 1997}$^,$\footnote{J. S. Pilgrim, C. S. Yeh, K. R. Berry, M. A. Duncan, J. Chem. Phys., 100, 7945, (1994)} Pulsed-field-ionization zero-kinetic-energy (PFI-ZEKE) photoelectron spectra of the X$^+$ $^2\Sigma^+$ ground state of MgKr$^+$ were recorded following single-photon excitation from the $a\; ^3\Pi_0$ metastable state of MgKr. Vibrational channel interactions enabled the observation of the lowest vibrational levels of MgKr$^+$ and the determination of an accurate value of the adiabatic ionization energy of metastable MgKr ($38183 \pm 2 \: \mathrm{cm}^{-1}$). Using isolated-core multiphoton Rydberg dissociation (ICMRD) spectroscopy,\footnote{M. G{\'{e}}n{\'{e}}vriez, D. Wehrli and F. Merkt, Mol. Phys. 118, e1703051 (2019)} spectra of several low-lying electronically excited states of MgKr$^+$ were observed that are associated with the Kr + Mg$^+ (nl)$ dissociation limits with $n=3,4$ and $l=s, p$ and $d$. These states may be regarded as the lowest members of Rydberg series converging on the ground state of MgKr$^{2+}$. These studies represent first steps towards studying the doubly charged cation MgKr$^{2+}$.

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

text

Language

eng

Handle URL

https://hdl.handle.net/2142/116859

DOI

https://doi.org/10.15278/isms.2022.WG04

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Copyright 2022 held by the authors

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