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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+.
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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
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Cho HG, Andrews LS. Matrix Infrared Spectroscopic Studies of B-NCCN, B- η2-(NC)-CN, NCBCN, CNBCN, CNBNC, and High-Order Products Produced in Reactions of Boron Atoms with Cyanogen. J Phys Chem A 2021; 125:6189-6197. [PMID: 34255520 DOI: 10.1021/acs.jpca.1c04437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The products in reactions of laser-ablated boron atoms with cyanogen in excess argon have been identified via investigation of the matrix spectra and their variation on photolysis, annealing, and isotopic substitutions. DFT calculations have been performed for the plausible products and reaction paths, providing helpful guides. B-NCCN and B-η2-(NC)-CN were observed in the original deposition spectra, but they disappear on photolysis with λ > 220 nm while more stable NCBCN, CNBCN, and CNBNC were produced. Besides these primary products, high-order products [(NC)2B-NCCN, (CN)(NC)B-NCCN, (CN)2B-NCCN, and (NC)2B-B(CN)2] were also observed, which increased in the later stage of annealing. Our calculations show that initially produced B-NCCN is interconvertible to B-η2-(NC)-CN and the more stable boron cyanide and isocyanide, consistent with the observed results. The formation of high-order products demonstrates that boron highly prefers the trivalent state in reactions with cyanogen, similar to aluminum.
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Affiliation(s)
- Han-Gook Cho
- Department of Chemistry, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, South Korea
| | - Lester S Andrews
- Department of Chemistry, University of Virginia, P.O. Box 400319, Charlottesville, Virginia 22904-4319, United States
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