1
|
Tsegaw YA, Li H, Andrews L, Cho HG, Voßnacker P, Beckers H, Riedel S. (Noble Gas) n -NC + Molecular Ions in Noble Gas Matrices: Matrix Infrared Spectra and Electronic Structure Calculations. Chemistry 2021; 28:e202103142. [PMID: 34897851 PMCID: PMC9299772 DOI: 10.1002/chem.202103142] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Indexed: 11/12/2022]
Abstract
An investigation of pulsed‐laser‐ablated Zn, Cd and Hg metal atom reactions with HCN under excess argon during co‐deposition with laser‐ablated Hg atoms from a dental amalgam target also provided Hg emissions capable of photoionization of the CN photo‐dissociation product. A new band at 1933.4 cm−1 in the region of the CN and CN+ gas‐phase fundamental absorptions that appeared upon annealing the matrix to 20 K after sample deposition, and disappeared upon UV photolysis is assigned to (Ar)nCN+, our key finding. It is not possible to determine the n coefficient exactly, but structure calculations suggest that one, two, three or four argon atoms can solvate the CN+ cation in an argon matrix with C−N absorptions calculated (B3LYP) to be between 2317.2 and 2319.8 cm−1. Similar bands were observed in solid krypton at 1920.5, in solid xenon at 1935.4 and in solid neon at 1947.8 cm−1. H13CN reagent gave an 1892.3 absorption with shift instead, and a 12/13 isotopic frequency ratio–nearly the same as found for 13CN+ itself in the gas phase and in the argon matrix. The CN+ molecular ion serves as a useful infrared probe to examine Ng clusters. The following ion reactions are believed to occur here: the first step upon sample deposition is assisted by a focused pulsed YAG laser, and the second step occurs on sample annealing: (Ar)2++CN→Ar+CN+→(Ar)nCN+.
Collapse
Affiliation(s)
- Yetsedaw A Tsegaw
- Anorganische Chemie, Institut fur Chemie und Biochemie, Freie Universitat Berlin, Fabeckstrasse 34-36, 14195, Berlin, Germany
| | - Hongmin Li
- Anorganische Chemie, Institut fur Chemie und Biochemie, Freie Universitat Berlin, Fabeckstrasse 34-36, 14195, Berlin, Germany
| | - Lester Andrews
- Department of Chemistry, University of Virginia, Charlottesville, Virginia, 22904, USA
| | - Han-Gook Cho
- Department of Chemistry, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon, 22012, South Korea
| | - Patrick Voßnacker
- Anorganische Chemie, Institut fur Chemie und Biochemie, Freie Universitat Berlin, Fabeckstrasse 34-36, 14195, Berlin, Germany
| | - Helmut Beckers
- Anorganische Chemie, Institut fur Chemie und Biochemie, Freie Universitat Berlin, Fabeckstrasse 34-36, 14195, Berlin, Germany
| | - Sebastian Riedel
- Anorganische Chemie, Institut fur Chemie und Biochemie, Freie Universitat Berlin, Fabeckstrasse 34-36, 14195, Berlin, Germany
| |
Collapse
|
2
|
Asvany O, Schlemmer S. Rotational action spectroscopy of trapped molecular ions. Phys Chem Chem Phys 2021; 23:26602-26622. [PMID: 34817492 DOI: 10.1039/d1cp03975j] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Rotational action spectroscopy is an experimental method in which rotational spectra of molecules, typically in the microwave to sub-mm-wave domain of the electromagnetic spectrum (∼1-1000 GHz), are recorded by action spectroscopy. Action spectroscopy means that the spectrum is recorded not by detecting the absorption of light by the molecules, but by the action of the light on the molecules, e.g., photon-induced dissociation of a chemical bond, a photon-triggered reaction, or photodetachment of an electron. Typically, such experiments are performed on molecular ions, which can be well controlled and mass-selected by guiding and storage techniques. Though coming with many advantages, the application of action schemes to rotational spectroscopy was hampered for a long time by the small energy content of a corresponding photon. Therefore, the first rotational action spectroscopic methods emerged only about one decade ago. Today, there exists a toolbox full of different rotational action spectroscopic schemes which are summarized in this review.
Collapse
Affiliation(s)
- Oskar Asvany
- I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937 Köln, Germany.
| | - Stephan Schlemmer
- I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937 Köln, Germany.
| |
Collapse
|
3
|
Mant B, Yurtsever E, González-Sánchez L, Wester R, Gianturco FA. Vibrational quenching of CN - in collisions with He and Ar. J Chem Phys 2021; 154:084305. [PMID: 33639742 DOI: 10.1063/5.0039854] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The vibrational quenching cross sections and corresponding low-temperature rate constants for the ν = 1 and ν = 2 states of CN-(1Σ+) colliding with He and Ar atoms have been computed ab initio using new three-dimensional potential energy surfaces. Little work has been carried out so far on low-energy vibrationally inelastic collisions for anions with neutral atoms. The cross sections and rates calculated at energies and temperatures relevant for both ion traps and astrochemical modeling are found by the present calculations to be even smaller than those of the similar C2 -/He and C2 -/Ar systems, which are in turn of the order of those existing for the collisions involving neutral diatom-atom systems. The implications of our finding in the present case mainly focus on the possible role of small computed rate constants in the dynamics of molecular cooling and the evolution of astrochemical modeling networks.
Collapse
Affiliation(s)
- Barry Mant
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25/3, 6020 Innsbruck, Austria
| | - Ersin Yurtsever
- Department of Chemistry, Koç University, Rumelifeneri yolu, Sariyer, TR-34450 Istanbul, Turkey
| | - Lola González-Sánchez
- Departamento de Química Física, University of Salamanca, Plaza de los Caídos sn, 37008 Salamanca, Spain
| | - Roland Wester
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25/3, 6020 Innsbruck, Austria
| | - Franco A Gianturco
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstr. 25/3, 6020 Innsbruck, Austria
| |
Collapse
|