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Shan S, Sun E, Gao Y, Li Z, Xu H, Yan B. An ab initio study on the electronic excited states and photodissociation mechanism of bromocarbene molecule. Phys Chem Chem Phys 2023. [PMID: 37305951 DOI: 10.1039/d3cp00985h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We used the internally contracted explicitly correlated multireference configuration interaction (icMRCI-F12) method combined with Davidson correction to conduct a high-precision ab initio study of CHBr. The spin-orbit coupling (SOC) is incorporated into the calculation. The 21 spin-free states split into 53 spin-coupled states of CHBr. The vertical transition energies and oscillator strengths are obtained of these states. The SOC effect on the equilibrium structures and the harmonic vibrational frequencies of the ground state X1A', the lowest triplet state a3A'' and the first excited singlet state A1A'' is investigated. The results reveal a significant effect of the SOC on the bond angle and the frequency of the bending mode of a3A''. The potential energy curves of electronic states of CHBr as functions of the H-C-Br bond angle, C-H bond length, and C-Br bond length, respectively, are also investigated. Based on the calculated results, the interactions between electronic states and photodissociation mechanism involved in CHBr in the ultraviolet region are explored. Our theoretical studies will shed light on the complicated interactions and dynamics of the electronic states of bromocarbenes.
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Affiliation(s)
- Shimin Shan
- School of Semiconductors and Physics, North University of China, Taiyuan 030051, China
| | - ErPing Sun
- College of Electronic and Information Engineering, Shandong University of Science and Technology, Qingdao 266590, China
| | - Yongquan Gao
- School of Semiconductors and Physics, North University of China, Taiyuan 030051, China
| | - Zirun Li
- School of Semiconductors and Physics, North University of China, Taiyuan 030051, China
| | - Haifeng Xu
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China.
| | - Bing Yan
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China.
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Chicharro DV, Hrodmarsson HR, Bouallagui A, Zanchet A, Loison JC, García GA, García-Vela A, Bañares L, Marggi Poullain S. Threshold Photoelectron Spectroscopy of the CH 2I, CHI, and CI Radicals. J Phys Chem A 2021; 125:6122-6130. [PMID: 34232644 PMCID: PMC8478278 DOI: 10.1021/acs.jpca.1c03874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
VUV photoionization of the CHnI radicals (with n = 0, 1, and 2) is investigated by means of synchrotron radiation coupled with a double imaging photoion-photoelectron coincidence spectrometer. Photoionization efficiencies and threshold photoelectron spectra (TPES) for photon energies ranging between 9.2 and 12.0 eV are reported. An adiabatic ionization energy (AIE) of 8.334 ± 0.005 eV is obtained for CH2I, which is in good agreement with previous results [8.333 ± 0.015 eV, Sztáray J. Chem. Phys. 2017, 147, 013944], while for CI an AIE of 8.374 ± 0.005 eV is measured for the first time and a value of ∼8.8 eV is estimated for CHI. Ab initio calculations have been carried out for the ground state of the CH2I radical and for the ground state and excited states of the radical cation CH2I+, including potential energy curves along the C-I coordinate. Franck-Condon factors are calculated for transitions from the CH2I(X̃2B1) ground state of the neutral radical to the ground state and excited states of the radical cation. The TPES measured for the CH2I radical shows several structures that correspond to the photoionization into excited states of the radical cation and are fully assigned on the basis of the calculations. The TPES obtained for the CHI is characterized by a broad structure peaking at 9.335 eV, which could be due to the photoionization from both the singlet and the triplet states and into one or more electronic states of the cation. A vibrational progression is clearly observed in the TPES for the CI radical and a frequency for the C-I stretching mode of 760 ± 60 cm-1 characterizing the CI+ electronic ground state has been extracted.
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Affiliation(s)
- David V Chicharro
- Departamento de Química Física (Unidad Asociada I+D+i al CSIC), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Helgi Rafn Hrodmarsson
- Synchrotron SOLEIL, L'Orme des Merisiers, St. Aubin, BP 48, 91192 Gif sur Yvette, France
| | - Aymen Bouallagui
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, C/Serrano, 123, 28006 Madrid, Spain.,Laboratoire de Spectroscopie Atomique, Moléculaire et Applications-LSAMA LR01ES09, Faculté des Sciences de Tunis, Université de Tunis El Manar, 2092 Tunis, Tunisia
| | - Alexandre Zanchet
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, C/Serrano, 123, 28006 Madrid, Spain
| | - Jean-Christophe Loison
- ISM, Université Bordeaux 1, CNRS, 351 cours de la Libération, 33405 Talence Cedex, France
| | - Gustavo A García
- Synchrotron SOLEIL, L'Orme des Merisiers, St. Aubin, BP 48, 91192 Gif sur Yvette, France
| | - Alberto García-Vela
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, C/Serrano, 123, 28006 Madrid, Spain
| | - Luis Bañares
- Departamento de Química Física (Unidad Asociada I+D+i al CSIC), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain.,Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanoscience), Cantoblanco, 28049 Madrid, Spain
| | - Sonia Marggi Poullain
- Departamento de Química Física (Unidad Asociada I+D+i al CSIC), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
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Khiri D, Hochlaf M, Maroulis G, Chambaud G. Spin–Orbit Effects in the Spectroscopy of the X2Π and a4Σ– Electronic States of Carbon Iodide, CI. J Phys Chem A 2018; 122:2353-2360. [DOI: 10.1021/acs.jpca.7b09240] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- D. Khiri
- Laboratoire Modélisation et Simulation Multi Echelle, Université Paris-Est, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée, France
| | - M. Hochlaf
- Laboratoire Modélisation et Simulation Multi Echelle, Université Paris-Est, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée, France
| | - G. Maroulis
- Department of Chemistry, University of Patras, GR-26500 Patras, Greece
| | - G. Chambaud
- Laboratoire Modélisation et Simulation Multi Echelle, Université Paris-Est, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée, France
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