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Gao HW, Choi HW, Hui J, Chen WJ, Kocheril GS, Wang LS. On the electronic structure and spin-orbit coupling of BiB from photoelectron imaging of cryogenically-cooled BiB- anion. J Chem Phys 2023; 159:114301. [PMID: 37712786 DOI: 10.1063/5.0170325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 08/28/2023] [Indexed: 09/16/2023] Open
Abstract
We report a study on the electronic structure and chemical bonding of the BiB molecule using high-resolution photoelectron imaging of cryogenically cooled BiB- anion. By eliminating all the vibrational hot bands, we can resolve the complicated detachment transitions due to the open-shell nature of BiB and the strong spin-orbit coupling. The electron affinity of BiB is measured to be 2.010(1) eV. The ground state of BiB- is determined to be 2Π(3/2) with a σ2π3 valence electron configuration, while the ground state of BiB is found to be 3Σ-(0+) with a σ2π2 electron configuration. Eight low-lying spin-orbit excited states [3Σ-(1), 1Δ(2), 1Σ+(0+), 3Π(2), 3Π(1), 1Π(1)], including two forbidden transitions, [3Π(0-) and 3Π(0+)], are observed for BiB as a result of electron detachment from the σ and π orbitals of BiB-. The angular distribution information from the photoelectron imaging is found to be critical to distinguish detachment transitions from the σ or π orbital for the spectral assignment. This study provides a wealth of information about the low-lying electronic states and spin-orbit coupling of BiB, demonstrating the importance of cryogenic cooling for obtaining well-resolved photoelectron spectra for size-selected clusters produced from a laser vaporization cluster source.
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Affiliation(s)
- Han-Wen Gao
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Hyun Wook Choi
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Jie Hui
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Wei-Jia Chen
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | - G Stephen Kocheril
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Lai-Sheng Wang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
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Kocheril GS, Gao HW, Wang LS. Observation of a long-lived triplet excited state and strong electron correlation effects in the copper oxide anion (CuO-) using cryogenic photoelectron imaging. J Chem Phys 2023; 158:236101. [PMID: 37318178 DOI: 10.1063/5.0151516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 05/30/2023] [Indexed: 06/16/2023] Open
Affiliation(s)
- G Stephen Kocheril
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Han-Wen Gao
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Lai-Sheng Wang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
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3
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Kocheril GS, Gao HW, Wang LS. Vibrationally- and rotationally-resolved photoelectron imaging of cryogenically-cooled SbO 2–. Mol Phys 2023. [DOI: 10.1080/00268976.2023.2182610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Affiliation(s)
| | - Han-Wen Gao
- Department of Chemistry, Brown University, Providence, RI, USA
| | - Lai-Sheng Wang
- Department of Chemistry, Brown University, Providence, RI, USA
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4
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Kocheril GS, Gao HW, Yuan DF, Wang LS. Photoelectron Imaging of Cryogenically-Cooled BiO- and BiO2- Anions. J Chem Phys 2022; 157:171101. [DOI: 10.1063/5.0127877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The advent of ion traps as cooling devices has revolutionized ion spectroscopy as it is now possible to efficiently cool ions vibrationally and rotationally to levels where truly high-resolution experiments are now feasible. Here we report the first results of a new experimental apparatus that couples a cryogenic 3D Paul trap with a laser vaporization cluster source for high-resolution photoelectron imaging of cold cluster anions. We have demonstrated the ability of the new apparatus to efficiently cool BiO- and BiO2- to minimize vibrational hot bands and allow high-resolution photoelectron images to be obtained. The electron affinities of BiO and BiO2 are measured accurately for the first time to be 1.492(1) and 3.281(1) eV, respectively. Vibrational frequencies for the ground states of BiO and BiO2 are reported, as well as those for the anions determined from temperature-dependent studies.
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Affiliation(s)
| | | | | | - Lai-Sheng Wang
- Department of Chemistry, Brown University, United States of America
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5
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Yuan DF, Liu Y, Qian CH, Kocheril GS, Zhang YR, Rubenstein BM, Wang LS. Polarization of Valence Orbitals by the Intramolecular Electric Field from a Diffuse Dipole-Bound Electron. J Phys Chem Lett 2020; 11:7914-7919. [PMID: 32898418 DOI: 10.1021/acs.jpclett.0c02514] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The diffuse electron in a dipole-bound state is spatially well separated from the valence electrons and is known to have negligible effects on the dipole-bound state's molecular structure. Here, we show that a dipole-bound state is observed in deprotonated 4-(2-phenylethynyl)-phenoxide anions, 348 cm-1 below the anion's detachment threshold. The photodetachment of the dipole-bound electron is observed to accompany a simultaneous shakeup process in valence orbitals in this aromatic molecular anion. This shakeup process is due to configuration mixing as a result of valence orbital polarization by the intramolecular electric field of the dipole-bound electron. This observation suggests that dipole-bound anions can serve as a new platform to probe how oriented electric fields influence the valence electronic structure of polyatomic molecules.
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Affiliation(s)
- Dao-Fu Yuan
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Yuan Liu
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Chen-Hui Qian
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - G Stephen Kocheril
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Yue-Rou Zhang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Brenda M Rubenstein
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Lai-Sheng Wang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
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Cheung LF, Czekner J, Kocheril GS, Wang LS. High-resolution photoelectron imaging of MnB 3 -: Probing the bonding between the aromatic B 3 cluster and 3d transition metals. J Chem Phys 2020; 152:244306. [PMID: 32610950 DOI: 10.1063/5.0013355] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The B3 triangular unit is a fundamental bonding motif in all boron compounds and nanostructures. The isolated B3 - cluster has a D3h structure with double σ and π aromaticity. Here, we report an investigation of the bonding between a B3 cluster and a 3d transition metal using high-resolution photoelectron imaging and computational chemistry. Photoelectron spectra of MnB3 - are obtained at six different photon energies, revealing rich vibrational information for the ground state detachment transition. The electron affinity of MnB3 is determined to be 1.6756(8) eV, and the most Franck-Condon-active mode observed has a measured frequency of 415(6) cm-1 due to the Mn-B3 stretch. Theoretical calculations show that MnB3 - has a C2v planar structure, with Mn coordinated to one side of the triangular B3 unit. The ground states of MnB3 - (6B2) and MnB3 (5B2) are found to have high spin multiplicity with a significant decrease in the Mn-B bond distances in the neutral due to the detachment of an Mn-B3 anti-bonding electron. The Mn atom is shown to have weak interactions with the B3 unit, which maintains its double aromaticity with relatively small structural changes from the bare B3 cluster. The bonding in MnB3 is compared with that in 5d MB3 clusters, where the strong metal-B3 interactions strongly change the structures and bonding in the B3 moiety.
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Affiliation(s)
- Ling Fung Cheung
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Joseph Czekner
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | - G Stephen Kocheril
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Lai-Sheng Wang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
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Cheung LF, Kocheril GS, Czekner J, Wang LS. The nature of the chemical bonding in 5d transition-metal diatomic borides MB (M = Ir, Pt, Au). J Chem Phys 2020; 152:174301. [DOI: 10.1063/5.0008484] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Ling Fung Cheung
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912, USA
| | - G. Stephen Kocheril
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912, USA
| | - Joseph Czekner
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912, USA
| | - Lai-Sheng Wang
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912, USA
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8
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Affiliation(s)
- Ling Fung Cheung
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - G. Stephen Kocheril
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Joseph Czekner
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Lai-Sheng Wang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
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9
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Affiliation(s)
- Ling Fung Cheung
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - G. Stephen Kocheril
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Joseph Czekner
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Lai-Sheng Wang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
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Abstract
The maximum bond order between two main-group atoms was known to be three. However, it has been suggested recently that there is quadruple bonding in C2 and analogous eight-valence electron species. While the quadruple bond in C2 has aroused some debates, an interesting question is: are main-group elements capable of forming quadruple bonds? Here we use photoelectron spectroscopy and computational chemistry to probe the electronic structure and chemical bonding in RhB2O- and RhB- and show that the boron atom engages in quadruple bonding with rhodium in RhB(BO)- and neutral RhB. The quadruple bonds consist of two π-bonds formed between the Rh 4dxz/4dyz and B 2px/2py orbitals and two σ-bonds between the Rh 4dz2 and B 2s/2pz orbitals. To confirm the quadruple bond in RhB, we also investigate the linear Rh≡B-H+ species and find a triple bond between Rh and B, which has a longer bond length, lower stretching frequency, and smaller bond dissociation energy in comparison with that of the Rh≣B quadruple bond in RhB.
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Affiliation(s)
- Ling Fung Cheung
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Teng-Teng Chen
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - G Stephen Kocheril
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Wei-Jia Chen
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Joseph Czekner
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Lai-Sheng Wang
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
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Abstract
Metallabenzenes are a class of molecules in which a CH unit in benzene is replaced by a functionalized transition-metal atom. While all-boron analogues of aromatic and antiaromatic hydrocarbons are well-known, there have not been any metallaboron analogs. We have produced and investigated two metal-doped boron clusters, ReB6- and AlB6-, using high-resolution photoelectron imaging and quantum chemical calculations. Vibrationally resolved photoelectron spectra have been obtained and compared with the theoretical results. The ReB6- cluster is found to be perfectly planar with a B-centered hexagonal structure (C2v, 1A1), while AlB6- is known to have a similar structure, but with a slightly out-of-plane distortion (Cs, 1A'). Chemical bonding analyses show that the closed-shell ReB6- is doubly σ- and π-aromatic, while AlB6- is known to be σ-aromatic and π-antiaromatic. The out-of-plane distortion in AlB6- is due to antiaromaticity, akin to the out-of-plane distortion of the prototypical antiaromatic cyclooctatetraene. The π-bonding in ReB6- is compared with that in both benzene and rhenabenzene [(CO)4ReC5H5], and remarkable similarities are found. Hence, ReB6- can be viewed as the first metallaboron analog of metallabenzenes and it may be viable for syntheses with suitable ligands.
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Affiliation(s)
- Ling Fung Cheung
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Joseph Czekner
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - G Stephen Kocheril
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Lai-Sheng Wang
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
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Avitall B, Kalinski A, Kocheril GS, Lizama KS, Coulombe N, Laske T. Characteristics of Ice Impedance Recorded From a Ring Electrode Placed at the Anterior Surface of the Cryoballoon: Novel Approach to Define Ice Formation and Pulmonary Vein Isolation. Circ Arrhythm Electrophysiol 2019; 11:e005949. [PMID: 29618477 DOI: 10.1161/circep.117.005949] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2017] [Accepted: 01/17/2018] [Indexed: 11/16/2022]
Abstract
BACKGROUND The success of cryoablation of the pulmonary vein isolation (PVI) is dependent on transmural and circumferential ice formation. We hypothesize that rising impedance recorded from a ring electrode placed 2 mm from the cryoballoon signifies ice formation covering the balloon surface and indicates ice expansion. The impedance level enables titration of the cryoapplication time to avoid extracardiac damage while ensuring PVI. METHODS AND RESULTS In 12 canines, a total of 57 pulmonary veins were targeted for isolation. Two cryoapplications were delivered per vein with a minimum of 90 and maximum of 180-second duration. Cryoapplication was terminated on reaching a 500 Ω change from baseline. Animals recovered 38±6 days post-procedure, and veins were assessed electrically for isolation. Heart tissue was histologically analyzed. Extracardiac structures were examined for damage. PVI was achieved in 100% of the veins if the impedance reached 500 Ω in <90 seconds with freeze time of 90 seconds. When 500 Ω was reached >90 to 180 seconds (142.60±29.3 seconds), 90% PVI was achieved. When the final impedance was between 200 and 500 Ω with 180 seconds of freeze time, PVI was achieved in 86.8%. For impedance of <200 Ω, PVI was achieved in 14%. No extracardiac damage was recorded. CONCLUSIONS Impedance rise of 500 Ω at <90 seconds with freeze time of 90 seconds resulted in 100% PVI. Impedance measurements from the nose of the balloon is a direct measure of ice formation on the balloon. It provides real-time feedback on the quality of the ablation and defines the cryoapplication termination time based on ice formation, limiting ice expansion to extracardiac tissues.
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Affiliation(s)
- Boaz Avitall
- Division of Cardiology, Department of Medicine, The University of Illinois at Chicago (B.A., A.K., G.S.K., K.S.L.); Medtronic Corporation, Montreal, Quebec, Canada (N.C.); and Medtronic, Minneapolis, MN (T.L.).
| | - Arthur Kalinski
- Division of Cardiology, Department of Medicine, The University of Illinois at Chicago (B.A., A.K., G.S.K., K.S.L.); Medtronic Corporation, Montreal, Quebec, Canada (N.C.); and Medtronic, Minneapolis, MN (T.L.)
| | - G Stephen Kocheril
- Division of Cardiology, Department of Medicine, The University of Illinois at Chicago (B.A., A.K., G.S.K., K.S.L.); Medtronic Corporation, Montreal, Quebec, Canada (N.C.); and Medtronic, Minneapolis, MN (T.L.)
| | - Ken S Lizama
- Division of Cardiology, Department of Medicine, The University of Illinois at Chicago (B.A., A.K., G.S.K., K.S.L.); Medtronic Corporation, Montreal, Quebec, Canada (N.C.); and Medtronic, Minneapolis, MN (T.L.)
| | - Nicolas Coulombe
- Division of Cardiology, Department of Medicine, The University of Illinois at Chicago (B.A., A.K., G.S.K., K.S.L.); Medtronic Corporation, Montreal, Quebec, Canada (N.C.); and Medtronic, Minneapolis, MN (T.L.)
| | - Timothy Laske
- Division of Cardiology, Department of Medicine, The University of Illinois at Chicago (B.A., A.K., G.S.K., K.S.L.); Medtronic Corporation, Montreal, Quebec, Canada (N.C.); and Medtronic, Minneapolis, MN (T.L.)
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Czekner J, Cheung LF, Kocheril GS, Kulichenko M, Boldyrev AI, Wang L. High‐Resolution Photoelectron Imaging of IrB
3
−
: Observation of a π‐Aromatic B
3
+
Ring Coordinated to a Transition Metal. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201902406] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Joseph Czekner
- Department of Chemistry Brown University 324 Brook Street Providence Rhode Island 02912 USA
| | - Ling Fung Cheung
- Department of Chemistry Brown University 324 Brook Street Providence Rhode Island 02912 USA
| | - G. Stephen Kocheril
- Department of Chemistry Brown University 324 Brook Street Providence Rhode Island 02912 USA
| | - Maksim Kulichenko
- Department of Chemistry and Biochemistry Utah State University 0300 Old Main Hill Logan Utah 84322 USA
| | - Alexander I. Boldyrev
- Department of Chemistry and Biochemistry Utah State University 0300 Old Main Hill Logan Utah 84322 USA
| | - Lai‐Sheng Wang
- Department of Chemistry Brown University 324 Brook Street Providence Rhode Island 02912 USA
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14
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Czekner J, Cheung LF, Kocheril GS, Kulichenko M, Boldyrev AI, Wang LS. High-Resolution Photoelectron Imaging of IrB 3 - : Observation of a π-Aromatic B 3 + Ring Coordinated to a Transition Metal. Angew Chem Int Ed Engl 2019; 58:8877-8881. [PMID: 31021049 DOI: 10.1002/anie.201902406] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Indexed: 11/12/2022]
Abstract
In a high-resolution photoelectron imaging and theoretical study of the IrB3 - cluster, two isomers were observed experimentally with electron affinities (EAs) of 1.3147(8) and 1.937(4) eV. Quantum calculations revealed two nearly degenerate isomers competing for the global minimum, both with a B3 ring coordinated with the Ir atom. The isomer with the higher EA consists of a B3 ring with a bridge-bonded Ir atom (Cs , 2 A'), and the second isomer features a tetrahedral structure (C3v , 2 A1 ). The neutral tetrahedral structure was predicted to be considerably more stable than all other isomers. Chemical bonding analysis showed that the neutral C3v isomer involves significant covalent Ir-B bonding and weak ionic bonding with charge transfer from B3 to Ir, and can be viewed as an Ir-(η3 -B3 + ) complex. This study provides the first example of a boron-to-metal charge-transfer complex and evidence of a π-aromatic B3 + ring coordinated to a transition metal.
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Affiliation(s)
- Joseph Czekner
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island, 02912, USA
| | - Ling Fung Cheung
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island, 02912, USA
| | - G Stephen Kocheril
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island, 02912, USA
| | - Maksim Kulichenko
- Department of Chemistry and Biochemistry, Utah State University, 0300 Old Main Hill, Logan, Utah, 84322, USA
| | - Alexander I Boldyrev
- Department of Chemistry and Biochemistry, Utah State University, 0300 Old Main Hill, Logan, Utah, 84322, USA
| | - Lai-Sheng Wang
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island, 02912, USA
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15
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Cheung LF, Czekner J, Kocheril GS, Wang LS. High resolution photoelectron imaging of boron-bismuth binary clusters: Bi2Bn− (n = 2–4). J Chem Phys 2019; 150:064304. [DOI: 10.1063/1.5084170] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Ling Fung Cheung
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912, USA
| | - Joseph Czekner
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912, USA
| | - G. Stephen Kocheril
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912, USA
| | - Lai-Sheng Wang
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912, USA
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16
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Czekner J, Cheung LF, Kocheril GS, Wang LS. Probing the coupling of a dipole-bound electron with a molecular core. Chem Sci 2018; 10:1386-1391. [PMID: 30809355 PMCID: PMC6354839 DOI: 10.1039/c8sc04771e] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 11/15/2018] [Indexed: 11/21/2022] Open
Abstract
A dipolar molecule can weakly bind an electron in a diffuse orbital. However, the spin-orbit coupling between this weakly bound electron and the electrons in the molecular core is not known. Here we probe this coupling using the linear C2P- anion with the 3Σ+ ground state, which possesses dipole-bound excited states because neutral C2P (2Π) has a sufficiently large dipole moment. Photodetachment spectroscopy and resonant photoelectron spectroscopy are used to probe the nature of the dipole-bound states. Two dipole-bound excited states are observed with a binding energy of 37 cm-1, corresponding to the two spin-orbit states of neutral C2P (2Π1/2 and 2Π3/2). The current study demonstrates that the weakly bound electron in the dipole-bound excited states of C2P- is not spin-coupled to the electrons in the C2P core and can be considered as a quasi-free electron.
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Affiliation(s)
- Joseph Czekner
- Brown University , Department of Chemistry , 324 Brook Street , Providence , RI 02912 , USA .
| | - Ling Fung Cheung
- Brown University , Department of Chemistry , 324 Brook Street , Providence , RI 02912 , USA .
| | - G Stephen Kocheril
- Brown University , Department of Chemistry , 324 Brook Street , Providence , RI 02912 , USA .
| | - Lai-Sheng Wang
- Brown University , Department of Chemistry , 324 Brook Street , Providence , RI 02912 , USA .
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Avitall B, Kalinski A, Kocheril GS, Laske TG, Coulombe N. Novel dyeless and fluoro-less approach to cryoballoon pulmonary vein occlusion assessment. Heart Rhythm 2017; 14:1241-1246. [PMID: 28506919 DOI: 10.1016/j.hrthm.2017.05.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Indexed: 11/19/2022]
Abstract
BACKGROUND Pulmonary vein (PV) occlusion is essential for PV isolation (PVI) using the cryoballoon. Currently occlusion is arbitrarily determined using fluoroscopy and contrast media. This study aimed to create an objective measure without utilizing excessive fluoroscopy and using no contrast media. OBJECTIVE To ensure PV occlusion without fluoroscopy and contrast dye. METHODS In 4 in vivo hearts 113 PV occlusions were tested with a 50% cold dye saline mix at 4°C. Occlusions were rated Good, Fair, and Poor by dye dissipation seen via fluoroscopy and correlated to temperature profiles recorded concurrently. Using these temperature profiles and no dye, cryoablations were placed in 12 additional hearts (56 unique veins, 126 occlusions). Two 180-second cryoablation applications were placed per vein with occlusion testing in between. PVI was defined by electrophysiology mapping, gross pathology, and histology after ≥4 weeks recovery. RESULTS Dye results were as follows: With Good, Fair, and Poor the maximal postinjection PV temperature dropped (ΔT) by 6.2 ± 4.2°C, 5.1 ± 3.7°C, and 2.4 ± 2.0°C. At 5 seconds post nadir temperature, injection temperature recovered 18% ± 14%, 36% ± 23%, and 50% ± 33%. Console thaw time to 0°C was 11.5 ± 4.8 seconds, 8.5 ± 2.1 seconds, and 4.3 ± 1.3 seconds. Success rate for PVI was 100%, 97%, and 0%. With no dye: ΔT: 7.7 ± 4.4°C, 5.8 ± 5.0°C, and 3.4 ± 2.3°C; % recovery at 5 seconds: 15% ± 12%, 31% ± 23%, 45% ± 30%; thaw time to 0°C: 11.9 ± 4.8 seconds, 10.5 ± 5.2 seconds, 6.0 ± 2.8 seconds; success rate: 97%, 91%, and 10%. CONCLUSION PV occlusion profile determination using 4°C cold saline injection is an effective approach to define the occlusion grade. Quality occlusions correlate strongly with PVI success.
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Perry AJ, Hodges JN, Markus CR, Kocheril GS, McCall BJ. Communication: High precision sub-Doppler infrared spectroscopy of the HeH+ ion. J Chem Phys 2014; 141:101101. [DOI: 10.1063/1.4895505] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Adam J. Perry
- Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA
| | - James N. Hodges
- Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA
| | - Charles R. Markus
- Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA
| | - G. Stephen Kocheril
- Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA
| | - Benjamin J. McCall
- Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA
- Departments of Astronomy and Physics, University of Illinois, Urbana, Illinois 61801, USA
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