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Qu Q, Cooper B, Yurchenko SN, Tennyson J. A spectroscopic model for the low-lying electronic states of NO. J Chem Phys 2021; 154:074112. [PMID: 33607908 DOI: 10.1063/5.0038527] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The rovibronic structure of A2Σ+, B2Π, and C2Π states of nitric oxide (NO) is studied with the aim of producing comprehensive line lists for its near ultraviolet spectrum. Empirical energy levels for the three electronic states are determined using a combination of the empirical measured active rotation-vibration energy level (MARVEL) procedure and ab initio calculations, and the available experimental data are critically evaluated. Ab initio methods that deal simultaneously with the Rydberg-like A2Σ+ and C2Π and the valence B2Π state are tested. Methods of modeling the sharp avoided crossing between the B2Π and C2Π states are tested. A rovibronic Hamiltonian matrix is constructed using the variational nuclear motion program Duo whose eigenvalues are fitted to the MARVEL. The matrix also includes coupling terms obtained from the refinement of the ab initio potential energy and spin-orbit coupling curves. Calculated and observed energy levels agree well with each other, validating the applicability of our method and providing a useful model for this open shell system.
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Affiliation(s)
- Qianwei Qu
- Department of Physics and Astronomy, University College London, London WC1E 6BT, United Kingdom
| | - Bridgette Cooper
- Department of Physics and Astronomy, University College London, London WC1E 6BT, United Kingdom
| | - Sergei N Yurchenko
- Department of Physics and Astronomy, University College London, London WC1E 6BT, United Kingdom
| | - Jonathan Tennyson
- Department of Physics and Astronomy, University College London, London WC1E 6BT, United Kingdom
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2
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Vanin AF. The Free-Radical Nature of Nitric Oxide Molecules as a Determinant of their Conversion to Nitrosonium Cations in Living Systems. Biophysics (Nagoya-shi) 2020. [DOI: 10.1134/s0006350920030239] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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3
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Vanin AF. What is the Mechanism of Nitric Oxide Conversion into Nitrosonium Ions Ensuring S-Nitrosating Processes in Living Organisms. Cell Biochem Biophys 2019; 77:279-292. [PMID: 31586291 DOI: 10.1007/s12013-019-00886-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 09/12/2019] [Indexed: 12/29/2022]
Abstract
Here, I present the data testifying that the conversion of free radical NO molecules to nitrosonium ions (NO+), which are necessary for the realization of one of NO biological effects (S-nitrosation), may occur in living organisms after binding NO molecules to loosely bound iron (Fe2+ ions) with the subsequent mutual one-electron oxidation-reduction of NO molecules (their disproportionation). Inclusion of thiol-containing substances as iron ligands into this process prevents hydrolysis of NO+ ions bound to iron thus providing the formation of stable dinitrosyl iron complexes (DNIC) with thiol ligands. Such complexes act in living organisms as donors of NO and NO+, providing stabilization and transfer of these agents via the autocrine and paracrine pathways. Without loosely bound iron (labile iron pool) and thiols participating in the DNIC formation, NO functioning as one of universal regulators of diverse metabolic processes would be impossible.
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Affiliation(s)
- Anatoly F Vanin
- N.N. Semenov Federal Research Center of Chemical Physics, Russian Academy of Sciences; Institute for Regenerative Medicine, I.M. Sechenov First Moscow State Medical University, Kosygin Str.4, Moscow, 119991, Russia.
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4
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Liu S, Yu YL, Wang JH. An atomic fluorescence spectrometer for monitoring nitrogen nutrients via NO vapor generation. Anal Chim Acta 2019; 1064:17-24. [DOI: 10.1016/j.aca.2019.02.057] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 02/22/2019] [Accepted: 02/24/2019] [Indexed: 10/27/2022]
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5
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Jayasundara N, Anunciado RB, Burgess E, Ashman S, Hüwel L. Ro-vibrational level dependence of the radiative lifetime of the Na 24 1Σ g + shelf state. J Chem Phys 2019; 150:064301. [PMID: 30769962 DOI: 10.1063/1.5053107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We report on calculations-using the LEVEL and BCONT programs by Le Roy, the latter of which is a version modified by B. McGeehan-of the dependence of the radiative lifetime of the Na2 sodium dimer 41Σg + shelf-state on the initial vibrational and rotational level for corresponding quantum numbers of 0 ≤ v ≤ 75 and 0 ≤ J ≤ 90, respectively. We also present experimental lifetime values for 43 < v < 64, averaged over J = 19 and 21, obtained by a delayed pump-probe method using a previously described molecular beam and time-of-flight apparatus. Our calculated results are based on all possible dipole allowed transitions (to the 21Σu +, 1(B)1Πu, and 1(A)1Σu + electronic states) terminating into bound as well as free final states. The shelf of the initial electronic state is a consequence of configuration interaction with the lowest Na+-Na- ion-pair potential and occurs, for the rotationless molecule, at the vibrational level v = 52. From the 41Σg + vibrational ground state to the shelf, the calculated lifetimes increase monotonically by a factor of about 3.8. Beyond around v = 52, depending on rotational excitation, the lifetimes decrease, settling to a value intermediate to the maximum and the minimum at v = 0. Within error bars and in the range available, our experimental data are compatible with these findings. In addition, our calculations reveal unusual and pronounced oscillatory variation of the lifetime with rotational quantum numbers for fixed vibrational levels above-but not below-the shelf. We discuss our findings in terms of the appropriate transition dipole moments and wavefunctions and provide a detailed comparison to recent lifetime calculations of sodium dimer ion-pair states [Sanli et al., J. Chem. Phys. 143, 104304 (2015)].
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Affiliation(s)
| | - Roy B Anunciado
- Physics Department, Wesleyan University, Middletown, Connecticut 06459, USA
| | - Emma Burgess
- Department of Engineering, Physics, and Systems, Providence College, Providence, Rhode Island 02918, USA
| | - Seth Ashman
- Department of Engineering, Physics, and Systems, Providence College, Providence, Rhode Island 02918, USA
| | - Lutz Hüwel
- Physics Department, Wesleyan University, Middletown, Connecticut 06459, USA
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Cheng J, Zhang H, Cheng X, Song X. Theoretical study of spectral parameters for the γ and β band systems of NO for atmosphere and high temperature. Mol Phys 2017. [DOI: 10.1080/00268976.2017.1336261] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Junxia Cheng
- Department of physics, College of Physical Science and Technology, Sichuan University, Chengdu, China
| | - Hong Zhang
- Department of physics, College of Physical Science and Technology, Sichuan University, Chengdu, China
- Key Laboratory of High Energy Density Physics and Technology of Ministry of Education, Institute of Atomic and Molecular Physics, Sichuan University, Chengdu, China
| | - Xinlu Cheng
- Key Laboratory of High Energy Density Physics and Technology of Ministry of Education, Institute of Atomic and Molecular Physics, Sichuan University, Chengdu, China
| | - Xiaoshu Song
- Department of physics, College of Physics and Electronic Science, Guizhou Normal University, Guizhou, China
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8
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Vanin AF, Borodulin RR, Mikoyan VD. Dinitrosyl iron complexes with natural thiol-containing ligands in aqueous solutions: Synthesis and some physico-chemical characteristics (A methodological review). Nitric Oxide 2017; 66:1-9. [PMID: 28216238 DOI: 10.1016/j.niox.2017.02.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 02/08/2017] [Accepted: 02/09/2017] [Indexed: 01/16/2023]
Abstract
Two approaches to the synthesis of dinitrosyl iron complexes (DNIC) with glutathione and l-cysteine in aqueous solutions based on the use of gaseous NO and appropriate S-nitrosothiols, viz., S-nitrosoglutathione (GS-NO) or S-nitrosocysteine (Cys-NO), respectively, are considered. A schematic representation of a vacuum unit for generation and accumulation of gaseous NO purified from the NO2 admixture and its application for obtaining aqueous solutions of DNIC in a Thunberg apparatus is given. To achieve this, a solution of bivalent iron in distilled water is loaded into the upper chamber of the Thunberg apparatus, while the thiol solution in an appropriate buffer (рН 7.4) is loaded into its lower chamber. Further steps, which include degassing, addition of gaseous NO, shaking of both solutions and formation of the Fe2+-thiol mixture, culminate in the synthesis of DNIC. The second approach consists in a stepwise addition of Fe2+ salts and nitrite to aqueous solutions of glutathione or cysteine. In the presence of Fe2+ and after the increase in рН to the physiological level, GS-NO or Cys-NO generated at acid media (pH < 4) are converted into DNIC with glutathione or cysteine. Noteworthy, irrespective of the procedure used for their synthesis DNIC with glutathione manifest much higher stability than DNIC with cysteine. The pattern of spin density distribution in iron-dinitrosyl fragments of DNIC characterized by the d7 electronic configuration of the iron atom and described by the formula Fe+(NO+)2 is unique in that it provides a plausible explanation for the ability of DNIC to generate NO and nitrosonium ions (NO+) and the peculiar characteristics of the EPR signal of their mononuclear form (M-DNIC).
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Affiliation(s)
- Anatoly F Vanin
- N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow, Russia; Institute of Regenerative Medicine, I.M. Sechenov First Moscow Medical University, Moscow, Russia.
| | - Rostislav R Borodulin
- N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow, Russia
| | - Vasak D Mikoyan
- N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow, Russia
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Stauffer HU, Roy S, Schmidt JB, Wrzesinski PJ, Gord JR. Two-color vibrational, femtosecond, fully resonant electronically enhanced CARS (FREE-CARS) of gas-phase nitric oxide. J Chem Phys 2016; 145:124308. [PMID: 27782654 DOI: 10.1063/1.4962834] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A resonantly enhanced, two-color, femtosecond time-resolved coherent anti-Stokes Raman scattering (CARS) approach is demonstrated and used to explore the nature of the frequency- and time-dependent signals produced by gas-phase nitric oxide (NO). Through careful selection of the input pulse wavelengths, this fully resonant electronically enhanced CARS (FREE-CARS) scheme allows rovibronic-state-resolved observation of time-dependent rovibrational wavepackets propagating on the vibrationally excited ground-state potential energy surface of this diatomic species. Despite the use of broadband, ultrafast time-resolved input pulses, high spectral resolution of gas-phase rovibronic transitions is observed in the FREE-CARS signal, dictated by the electronic dephasing timescales of these states. Analysis and computational simulation of the time-dependent spectra observed as a function of pump-Stokes and Stokes-probe delays provide insight into the rotationally resolved wavepacket motion observed on the excited-state and vibrationally excited ground-state potential energy surfaces of NO, respectively.
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Affiliation(s)
- Hans U Stauffer
- Spectral Energies, LLC, 5100 Springfield St., Suite 301, Dayton, Ohio 45431, USA
| | - Sukesh Roy
- Spectral Energies, LLC, 5100 Springfield St., Suite 301, Dayton, Ohio 45431, USA
| | - Jacob B Schmidt
- Spectral Energies, LLC, 5100 Springfield St., Suite 301, Dayton, Ohio 45431, USA
| | - Paul J Wrzesinski
- Aerospace Systems Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio 45433, USA
| | - James R Gord
- Aerospace Systems Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio 45433, USA
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10
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Endo T, Matsuda A, Fushitani M, Yasuike T, Tolstikhin OI, Morishita T, Hishikawa A. Imaging Electronic Excitation of NO by Ultrafast Laser Tunneling Ionization. PHYSICAL REVIEW LETTERS 2016; 116:163002. [PMID: 27152798 DOI: 10.1103/physrevlett.116.163002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Indexed: 06/05/2023]
Abstract
Tunneling-ionization imaging of photoexcitation of NO has been demonstrated by using few-cycle near-infrared intense laser pulses (8 fs, 800 nm, 1.1×10^{14} W/cm^{2}). The ion image of N^{+} fragment ions produced by dissociative ionization of NO in the ground state, NO (X^{2}Π,2π)→NO^{+}+e^{-}→N^{+}+O+e^{-}, exhibits a characteristic momentum distribution peaked at 45° with respect to the laser polarization direction. On the other hand, a broad distribution centered at ∼0° appears when the A^{2}Σ^{+} (3sσ) excited state is prepared as the initial state by deep-UV photoexcitation. The observed angular distributions are in good agreement with the corresponding theoretical tunneling ionization yields, showing that the fragment anisotropy reflects changes of the highest-occupied molecular orbital by photoexcitation.
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Affiliation(s)
- Tomoyuki Endo
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8602, Japan
| | - Akitaka Matsuda
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8602, Japan
| | - Mizuho Fushitani
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8602, Japan
| | | | - Oleg I Tolstikhin
- Moscow Institute of Physics and Technology, Dolgoprudny 141700, Russia
| | - Toru Morishita
- Institute for Advanced Science, The University of Electro-Communications, 1-5-1 Chofu-ga-oka, Chofu, Tokyo 182-8585, Japan
| | - Akiyoshi Hishikawa
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8602, Japan
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11
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Burgos Paci MA, Few J, Gowrie S, Hancock G. Products of the quenching of NO A 2Σ+ (v = 0) by N2O and CO2. Phys Chem Chem Phys 2013; 15:2554-64. [PMID: 23296078 DOI: 10.1039/c2cp43878j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Collisional quenching of NO A (2)Σ(+) (v = 0) by N(2)O and CO(2) has been studied through measurements of vibrationally excited products by time resolved Fourier transform infrared emission. In both cases vibrationally excited NO X (2)Π (v) is seen and quantified in levels v≥ 2 with distributions which are close to statistical. However the quantum yields to produce these levels are markedly different for the two quenchers. For CO(2) such quenching accounts for only ca. 26% of the total: for N(2)O it is ca. 85%. Far more energy is seen in the internal modes of the CO(2) product than those of N(2)O. The results are rationalised in terms of cleavage of the N(2)-O bond being dominant in the latter case, with either a similar O atom production or a specific channel producing almost exclusively NO in low vibrational levels (v = 0,1) for quenching by CO(2). Minor reactive channels yielding NO(2) are seen in both cases, and O((1)D) is observed with low quantum yield in the reaction with N(2)O. The results are discussed in terms of previous models of the quenching processes, and are consistent with the very high yield of NO X (2)Π (v = 0) previously observed by laser induced fluorescence for quenching of NO A (2)Σ(+) (v = 0) by CO(2).
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12
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Borodulin RR, Kubrina LN, Mikoyan VD, Poltorakov AP, Shvydkiy VО, Burbaev DS, Serezhenkov VA, Yakhontova ER, Vanin AF. Dinitrosyl iron complexes with glutathione as NO and NO+ donors. Nitric Oxide 2013; 29:4-16. [DOI: 10.1016/j.niox.2012.11.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 11/15/2012] [Accepted: 11/28/2012] [Indexed: 11/29/2022]
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13
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Zhai X, Ding Y, Peng Z, Luo R. Concentration measurement of NO using self-absorption spectroscopy of the γ band system in a pulsed corona discharge. APPLIED OPTICS 2012; 51:4605-4611. [PMID: 22781235 DOI: 10.1364/ao.51.004605] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Accepted: 05/15/2012] [Indexed: 06/01/2023]
Abstract
Nitric oxide (NO) concentrations were measured using the γ band system spectrum based on the strong self-absorption effect of NO in pulsed corona discharges. The radiative transitional intensities of the NO γ band were simulated based on the theory of molecular spectroscopy. The intensities of some bands, especially γ(0,0) and γ(1,0), are weakened by the self-absorption. The correlations between the spectral self-absorption intensities and NO concentration were validated using a modified Beer-Lambert law with a combined factor K relating the branching ratio and the NO concentration, and a nonlinear index α that is applicable to the broadband system. Optical emissive spectra in pulsed corona discharges in NO and N2/He mixtures were used to evaluate the two parameters for various conditions. Good agreement between the experimental and theoretical results verifies the self-absorption behavior seen in the UV spectra of the NO γ bands.
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Affiliation(s)
- Xiaodong Zhai
- Department of Thermal Engineering, State Key Laboratory of Power Systems, Tsinghua University, Beijing, China
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Cooper R, Bartels C, Kandratsenka A, Rahinov I, Shenvi N, Golibrzuch K, Li Z, Auerbach DJ, Tully JC, Wodtke AM. Multiquantum Vibrational Excitation of NO Scattered from Au(111): Quantitative Comparison of Benchmark Data to Ab Initio Theories of Nonadiabatic Molecule-Surface Interactions. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201201168] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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15
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Cooper R, Bartels C, Kandratsenka A, Rahinov I, Shenvi N, Golibrzuch K, Li Z, Auerbach DJ, Tully JC, Wodtke AM. Multiquantum Vibrational Excitation of NO Scattered from Au(111): Quantitative Comparison of Benchmark Data to Ab Initio Theories of Nonadiabatic Molecule-Surface Interactions. Angew Chem Int Ed Engl 2012; 51:4954-8. [DOI: 10.1002/anie.201201168] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2012] [Indexed: 11/07/2022]
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16
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Tanjaroon C, Reeve SW, Ford A, Murry WD, Lyon K, Yount B, Britton D, Burns WA, Allen SD, Bruce Johnson J. Picosecond rotationally resolved stimulated emission pumping spectroscopy of nitric oxide. Chem Phys 2012. [DOI: 10.1016/j.chemphys.2011.11.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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17
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HAN YONGCHANG, WANG SENMING, YUAN KAIJUN, CONG SHULIN. THE EFFECT OF THE COUPLING BETWEEN VALENCE STATE B2Π AND RYDBERG STATE C2Π ON THE ABSORPTION SPECTRUM OF THE NO MOLECULE. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2011. [DOI: 10.1142/s021963360600274x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The effect of the coupling between the valence state B 2Π and the Rydberg state C 2Π on the absorption spectrum of the NO molecule is studied by using the quantum wave packet dynamics method. The results show that the coupling between the valence state B 2Π and the Rydberg state C 2Π affects the C 2Π ← X 2Π absorption spectrum both in the intensity and on the location of spectrum peaks. The dynamics of the wave packet of the excited states is also described. One part of the wave packet evolves on the Rydberg state C 2Π and the other is trapped in the valence state B 2Π.
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Affiliation(s)
- YONG-CHANG HAN
- Department of Physics, Dalian University of Technology, Dalian 116024, People's Republic of China
| | - SEN-MING WANG
- Department of Physics, Dalian University of Technology, Dalian 116024, People's Republic of China
| | - KAI-JUN YUAN
- Department of Physics, Dalian University of Technology, Dalian 116024, People's Republic of China
| | - SHU-LIN CONG
- Department of Physics, Dalian University of Technology, Dalian 116024, People's Republic of China
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18
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Zhang G, Jin Y. Photo-acoustic detection on electronic quenching rate constants of NO excited states. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2011; 78:1567-1571. [PMID: 21388865 DOI: 10.1016/j.saa.2011.01.054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Revised: 01/22/2011] [Accepted: 01/30/2011] [Indexed: 05/30/2023]
Abstract
The electronic quenching rate constants of NO A(2)Σ (υ'=0, 1), E(2)Σ (υ'=2, 3, 4) and F(2)Δ (υ'=1, 2, 3) states by gas air are reported. The experiments were carried out by measuring the total fluorescence intensity of A(2)Σ (υ'=0, 1)→X(2)Π (υ″) transition at various air pressures. It gives the Stern-Volmer plots. The quenching rate constants of A(2)Σ (υ'=0, 1) states are obtained from the slope of Stern-Volmer plots and the known radiative lifetime. Based on the primary results of the work, we have measured the quenching rate constants of high excited E(2)Σ (υ'=2, 3, 4), F(2)Δ (υ'=1, 2, 3) states for the first time with the technique of photo-acoustic (PA) spectroscopy. It is shown that the electronic quenching rate constants of NO E (υ') and F (υ') states are in the order of 10(-10)cm(3)/molecules. They are much larger than those of A(2)Σ (υ') state, whose rate constants are in the order of 10(-13)cm(3)/molecules. For E (υ') and F (υ') states, it is also found that the quenching rate constants increase with the vibrational energy levels. Similar result has been reported also for A(2)Σ (υ'≥2) states in existing literatures. The agreement indicates the potential use of PA spectroscopy for measuring the electronic quenching rate.
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Affiliation(s)
- Guiyin Zhang
- School of Mathematics and Physics, North China Electric Power University, Baoding 071003, China.
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19
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Tokel O, Chen J, Ulrich CK, Houston PL. O((1)D) + N(2)O reaction: NO vibrational and rotational distributions. J Phys Chem A 2010; 114:11292-7. [PMID: 20735039 DOI: 10.1021/jp1042377] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The O((1)D) + N(2)O → 2NO(X (2)Π) reaction has been studied in a molecular beam experiment in which O(3) and N(2)O were coexpanded. The precursor O((1)D) was prepared by O(3) photodissociation at 266 nm, and the NO(X (2)Π) molecules born from the reaction as the O((1)D) recoiled out of the beam were detected by 1+1 REMPI over the 220-246 nm probe laser wavelength range. The resulting spectrum was simulated to extract rotational and vibrational distributions of the NO(X (2)Π) molecules. The product rotational distribution is found to be characterized by a constant rotational temperature of ≈4500 K for all observed bands, v = 0-9. An inverted vibrational distribution is observed. A consistent explanation of this and previous experimental results is possible if there are two channels for the reaction, one producing a nearly statistical vibrational distribution for low O((1)D)-N(2)O relative velocity collisions and a second producing the inverted distribution observed here for high relative velocity collisions. The former might correspond to an insertion/complex-formation reaction, while the latter might correspond to a stripping reaction. Velocity relaxation of the O((1)D) is argued to compete strongly with reaction in most bulb studies, so that these studies see predominantly the nearly statistical distribution. In contrast, the beam experiments do not detect the part of the vibrational distribution produced in low relative velocity reactions because the O((1)D) is not relaxed from its initial velocity before it either reacts or leaves the beam.
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Affiliation(s)
- O Tokel
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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Chai N, Lucht RP, Kulatilaka WD, Roy S, Gord JR. Electronic-resonance-enhanced coherent anti-Stokes Raman scattering of nitric oxide: saturation and Stark effects. J Chem Phys 2010; 133:084310. [PMID: 20815572 DOI: 10.1063/1.3474702] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A theoretical analysis of electronic-resonance-enhanced (ERE) coherent anti-Stokes Raman scattering (CARS) of NO is described. The time-dependent density-matrix equations for the nonlinear ERE-CARS process are derived and manipulated into a form suitable for direct numerical integration. In the ERE-CARS configuration considered in this paper, the pump and Stokes beams are far from electronic-resonance. The visible 532 and 591 nm laser beams are used to excite Q-branch Raman resonances in the vibrational bands of the X (2)Pi electronic state of NO. An ultraviolet probe beam at 236 nm is used to excite P-, Q-, or R-branch transitions in the (v'=0, v"=1) band of the A (2)Sigma(+)-X (2)Pi electronic system of NO molecule. Experimental spectra are obtained either by scanning the ultraviolet probe beam while keeping the Stokes frequency fixed (probe scans) or by scanning the Stokes frequency while keeping the probe frequency fixed (Stokes scans). The calculated NO ERE-CARS spectra are compared with experimental spectra, and good agreement is observed between theory and experiment in terms of spectral peak locations and relative intensities. The effects of saturation of the two-photon Raman-resonant Q-branch transitions, the saturation of a one-photon electronic-resonant P-, Q-, or R-branch transitions in the A (2)Sigma(+)-X (2)Pi electronic system, and the coupling of these saturation processes are investigated. The coupling of the saturation processes for the probe and Raman transitions is complex and exhibits behavior similar to that observed in the electromagnetic induced transparency process. The probe scan spectra are significantly affected by Stark broadening due to the interaction of the pump and Stokes radiation with single-photon resonances between the upper vibration-rotation probe level in the A (2)Sigma(+) electronic levels and vibration-rotation levels in higher lying electronic levels. The ERE-CARS signal intensity is found to be much less sensitive to variations in the collisional dephasing rates under saturation conditions.
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Affiliation(s)
- Ning Chai
- School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, USA
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Wynn CM, Palmacci S, Kunz RR, Rothschild M. Noncontact detection of homemade explosive constituents via photodissociation followed by laser-induced fluorescence. OPTICS EXPRESS 2010; 18:5399-5406. [PMID: 20389555 DOI: 10.1364/oe.18.005399] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Noncontact detection of the homemade explosive constituents urea nitrate, nitromethane and ammonium nitrate is achieved using photodissociation followed by laser-induced fluorescence (PD-LIF). Our technique utilizes a single ultraviolet laser pulse (approximately 7 ns) to vaporize and photodissociate the condensed-phase materials, and then to detect the resulting vibrationally-excited NO fragments via laser-induced fluorescence. PD-LIF excitation and emission spectra indicate the creation of NO in vibrationally-excited states with significant rotational energy, useful for low-background detection of the parent compound. The results for homemade explosives are compared to one another and 2,6-dinitrotoluene, a component present in many military explosives.
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Affiliation(s)
- C M Wynn
- Lincoln Laboratory, Massachusetts Institute of Technology, 244 Wood Street, Lexington, MA 02420, USA.
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Cooper R, Rahinov I, Li Z, Matsiev D, Auerbach DJ, Wodtke AM. Vibrational overtone excitation in electron mediated energy transfer at metal surfaces. Chem Sci 2010. [DOI: 10.1039/c0sc00141d] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Standoff detection of nitrotoluenes using 213-nm amplified spontaneous emission from nitric oxide. Anal Bioanal Chem 2009; 395:349-55. [DOI: 10.1007/s00216-009-2990-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2009] [Revised: 07/16/2009] [Accepted: 07/17/2009] [Indexed: 11/26/2022]
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Patnaik AK, Roy S, Gord JR, Lucht RP, Settersten TB. Effects of collisions on electronic-resonance-enhanced coherent anti-Stokes Raman scattering of nitric oxide. J Chem Phys 2009; 130:214304. [DOI: 10.1063/1.3137106] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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Settersten TB, Patterson BD, Carter CD. Collisional quenching of NO A 2Sigma+(v' = 0) between 125 and 294 K. J Chem Phys 2009; 130:204302. [PMID: 19485444 DOI: 10.1063/1.3138178] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
We report measurements of the temperature-dependent cross sections for the quenching of fluorescence from the A (2)Sigma(+)(v(')=0) state of NO for temperatures between 125 and 294 K. Thermally averaged cross sections were measured for quenching by NO(X (2)Pi), N(2), O(2), and CO in a cryogenically cooled gas flow cell. Picosecond laser-induced fluorescence was time resolved, and the thermally averaged quenching cross sections were determined from the dependence of the fluorescence decay rate on the quencher-gas pressure. These measurements extend to lower temperature the range of previously published results for NO and O(2) and constitute the first reported measurements of the N(2) and CO cross sections for temperatures below 294 K. Between 125 and 294 K, a negative temperature dependence is observed for quenching by NO, O(2), and CO, implicating collision-complex formation in all three cases. Over the same temperature range, a constant, nonzero cross section is measured for quenching by N(2). Updated empirical models for the temperature dependence of the cross sections between 125 and 4500 K are recommended based on weighted least-squares fits to the current low-temperature results and previously published measurements at higher temperature. The results of over 250 measurements presented here indicate that the collisionless lifetime of NO A (2)Sigma(+)(v(')=0) is approximately 192 ns.
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Affiliation(s)
- Thomas B Settersten
- Combustion Research Facility, Sandia National Laboratories, Livermore, California 94551, USA.
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Gödecke N, Maul C, Chichinin AI, Kauczok S, Gericke KH. Complete characterization of the constrained geometry bimolecular reaction O([sup 1]D)+N[sub 2]O→NO+NO by three-dimensional velocity map imaging. J Chem Phys 2009; 131:054307. [DOI: 10.1063/1.3194292] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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27
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Settersten TB, Patterson BD, Humphries WH. Radiative lifetimes of NO A [sup 2]Σ[sup +](v[sup ʹ]=0,1,2) and the electronic transition moment of the A [sup 2]Σ[sup +]−X [sup 2]Π system. J Chem Phys 2009. [DOI: 10.1063/1.3227520] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
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Wynn CM, Palmacci S, Kunz RR, Clow K, Rothschild M. Detection of condensed-phase explosives via laser-induced vaporization, photodissociation, and resonant excitation. APPLIED OPTICS 2008; 47:5767-5776. [PMID: 19122718 DOI: 10.1364/ao.47.005767] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We investigate the remote detection of explosives via a technique that vaporizes and photodissociates the condensed-phase material and detects the resulting vibrationally excited NO fragments via laser-induced fluorescence. The technique utilizes a single 7 ns pulse of a tunable laser near 236.2 nm to perform these multiple processes. The resulting blue-shifted fluorescence (226 nm) is detected using a photomultiplier and narrowband filter that strongly block the scatter of the pump laser off the solid media while passing the shorter wavelength photons. Various nitro-bearing compounds, including 2,6-dinitrotoluene (DNT), 2,4,6-trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) were detected with a signal-to-noise of 25 dB. The effects of laser fluence, wavelength, and sample morphology were examined.
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Affiliation(s)
- C M Wynn
- Lincoln Laboratory, Massachusetts Institute of Technology, 244 Wood Street, Lexington, Massachusetts 02420, USA.
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Mitscherling C, Lauenstein J, Maul C, Veselov AA, Vasyutinskii OS, Gericke KH. Non-invasive and isotope-selective laser-induced fluorescence spectroscopy of nitric oxide in exhaled air. J Breath Res 2007; 1:026003. [DOI: 10.1088/1752-7155/1/2/026003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Oberst M, Münch H, Halfmann T. Efficient coherent population transfer among three states in NO molecules by Stark-Chirped rapid adiabatic passage. PHYSICAL REVIEW LETTERS 2007; 99:173001. [PMID: 17995324 DOI: 10.1103/physrevlett.99.173001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2007] [Indexed: 05/25/2023]
Abstract
We present the experimental demonstration of a novel, efficient, and selective technique to prepare population inversion. The technique is an extension of Stark-chirped rapid adiabatic passage (SCRAP), i.e., SCRAP among three states. In this process a Lambda-type quantum system is driven by two laser pulses, the pump and Stokes pulses, which are appropriately detuned from transition frequencies. A third laser pulse induces a dynamic Stark shift in the upper energy level, and the timing of all three pulses is controlled in order to prepare population inversion between the two lower states in the Lambda-type level scheme. Our data on population transfer in nitric oxide (NO) molecules clearly show that SCRAP among three states provides an advantageous alternative to such techniques as stimulated Raman adiabatic passage.
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Affiliation(s)
- Martin Oberst
- Institute for Applied Physics, TU Darmstadt, Schlossgartenstrasse 7, 64289 Darmstadt, Germany.
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Settersten TB, Patterson BD, Gray JA. Temperature- and species-dependent quenching of NO A 2Sigma+(v'=0) probed by two-photon laser-induced fluorescence using a picosecond laser. J Chem Phys 2007; 124:234308. [PMID: 16821919 DOI: 10.1063/1.2206783] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We report improved measurements of the temperature-dependent cross sections for the quenching of fluorescence from the A 2Sigma+(v'=0) state of NO. Cross sections were measured for gas temperatures ranging from 294 to 1300 K for quenching by NO(X (2)Pi), H(2)O, CO(2), O(2), CO, N(2), and C(2)H(2). The A 2Sigma+(v'=0) state was populated via two-photon excitation with a picosecond laser at 454 nm, and the decay rate of the fluorescence originating from A 2Sigma+(v'=0) was measured directly. Thermally averaged quenching cross sections were determined from the dependence of the fluorescence decay rate on the quencher gas pressure. Our measurements are compared to previous measurements and models of the quenching cross sections, and new empirical fits to the data are presented. Our new cross-section data enable predictions in excellent agreement with prior measurements of the fluorescence lifetime in an atmospheric-pressure methane-air diffusion flame. The agreement resolves discrepancies between the lifetime measurements and predictions based on the previous quenching models, primarily through improved models for the quenching by H(2)O, CO(2), and O(2) at temperatures less than 1300 K.
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Affiliation(s)
- Thomas B Settersten
- Combustion Research Facility, Sandia National Laboratories, Livermore, CA 94551, USA.
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Conde AP, Brandt L, Halfmann T. Trace isotope detection enhanced by coherent elimination of power broadening. PHYSICAL REVIEW LETTERS 2006; 97:243004. [PMID: 17280278 DOI: 10.1103/physrevlett.97.243004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2006] [Indexed: 05/13/2023]
Abstract
The selectivity and spectral resolution of traditional laser-based trace isotope analysis, i.e., resonance ionization mass spectrometry (RIMS), is limited by power broadening of the radiative transition. We use the fact that power broadening does not occur in coherently driven quantum systems when the probing and excitation processes are temporally separated to demonstrate significant improvement of trace element detection, even under conditions of strong signals. Specifically, we apply a coherent variant of RIMS to the detection of traces of molecular nitric oxide (NO) isobars. For large laser intensities, the detected isotope signal can be increased by almost 1 order of magnitude without any loss in spectral resolution.
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Affiliation(s)
- Alvaro Peralta Conde
- Fachbereich Physik der Universität, Erwin-Schrödinger-Strasse, D-67653 Kaiserslautern, Germany.
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White JD, Chen J, Matsiev D, Auerbach DJ, Wodtke AM. Vibrationally promoted electron emission from low work-function metal surfaces. J Chem Phys 2006; 124:64702. [PMID: 16483224 DOI: 10.1063/1.2166360] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
We observe electron emission when vibrationally excited NO molecules with vibrational state v, in the range of 9 < or = v < or =18, are scattered from a Cs-dosed Au surface. The quantum efficiency increases strongly with v, increasing up to 10(-2) electrons per NO (v) collision, a value several orders of magnitude larger than that observed in experiments with similar molecules in the ground vibrational state. The electron emission signal, as a function of v, has a threshold where the vibrational excitation energy slightly exceeds the surface work function. This threshold behavior strongly suggests that we are observing the direct conversion of NO vibrational energy into electron kinetic energy. Several potential mechanisms for the observed electron emission are explored, including (1) vibrational autodetachment, (2) an Auger-type two-electron process, and (3) vibrationally promoted dissociation. The results of this work provide direct evidence for nonadiabatic energy-transfer events associated with large amplitude vibrational motion at metal surfaces.
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Affiliation(s)
- Jason D White
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, 93106-9510, USA
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Yoshino K, Thorne AP, Murray JE, Cheung ASC, Wong AL, Imajo T. The application of a vacuum-ultraviolet Fourier transform spectrometer and synchrotron-radiation source to measurements of bands of NO. VII. The final report. J Chem Phys 2006; 124:054323. [PMID: 16468885 DOI: 10.1063/1.2138029] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Photoabsorption measurements of NO bands have been made by vacuum-ultraviolet Fourier transform spectrometry with a resolution of 0.12 cm(-1) in the wavelength region of 166.2-196.2 nm. Accurate line positions are obtained for the delta(upsilon,0) bands with upsilon=2, 3, the epsilon(upsilon,0) bands with upsilon=2, 3, and the beta(upsilon,0) bands with upsilon=10,12,14. Absolute term values are found for the corresponding upper levels C(2,3), D(2,3), and B(10,12,14). Accurate rotational line integrated cross sections have also been obtained for the lines in these bands. Integrated cross sections reported in our earlier papers [J. Chem. Phys. 109, 1751 (1998); 112, 2251 (2000); 115, 3719 (2001); 116, 155 (2002); 117, 10621 (2002); 119, 8373 (2003)] have been revised, and the results reported here comprise the delta(upsilon,0) bands with upsilon=0-3, the epsilon(upsilon,0) bands with upsilon=0-3, the beta(upsilon,0) bands with upsilon=6,7,9-12,14, and the gamma(3,0) band. For each band, the band oscillator strength is obtained from the sum of the line strengths of all rotational lines, and these are compared with other published values.
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Affiliation(s)
- K Yoshino
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA.
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Settersten TB, Patterson BD, Kronemayer H, Sick V, Schulz C, Daily JW. Branching ratios for quenching of nitric oxide A2Σ+(ν′ = 0) to X2Π(ν″ = 0). Phys Chem Chem Phys 2006; 8:5328-38. [DOI: 10.1039/b608619e] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Gattinger RL, Degenstein DA, Llewellyn EJ. Optical Spectrograph and Infra-Red Imaging System (OSIRIS) observations of mesospheric OH A2Σ+-X2Π 0-0 and 1-1 band resonance emissions. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jd006369] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Velasco AM, Martín * I, Lavín C, Bustos E. Radiative lifetimes for the A2Σ+(v′ = 0–7) and D2Σ+(v′ = 0–5) Rydberg states of NO. Mol Phys 2005. [DOI: 10.1080/00268970500052296] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Wang SM, Cong SL, Yuan KJ, Yu J. Probing wave packet dynamics of B2Π and C2Π states of NO molecule with time- and energy-resolved photoelectron spectra. Chem Phys Lett 2005. [DOI: 10.1016/j.cplett.2004.11.118] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Schmidt TW, López-Martens RB, Roberts G. Intense-field modulation of NO2 multiphoton dissociation dynamics. J Chem Phys 2004; 121:4133-42. [PMID: 15332960 DOI: 10.1063/1.1775768] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We report on the dynamics of multiphoton excitation and dissociation of NO(2) at wavelengths between 395 and 420 nm and intensities between 4 and 10 TW cm(-2). The breakup of the molecule is monitored by NO A (2)Sigma(+)n(')=1,0-->X (2)Pi(r)n(")=0 fluorescence as a function of time delay between the driving field and a probe field which depletes the emission. It is found that generation of n(')=0 and 1 NO A (2)Sigma(+) results in different fluorescence modulation patterns due to the intense probe field. The dissociation dynamics are interpreted in terms of nuclear motions over light-induced potentials formed by coupling of NO(2) valence and Rydberg states to the applied field. Based on this model, it is argued that the time and intensity dependences of A (2)Sigma(+)n(')=0-->X (2)Pi(r)n(")=0 fluorescence are consistent with delayed generation of NO A (2)Sigma(+)n(')=0 via a light-induced bond-hardening brought about by the transient coupling of the dressed A (2)B(2) and Rydberg 3ssigma (2)Sigma(g) (+) states of the parent molecule. The increasingly prompt decay of A (2)Sigma(+)n(')=1-->X (2)Pi(r)n(")=0 fluorescence with increasing intensity, on the other hand, is consistent with a direct surface crossing between the X (2)A(1) and 3ssigma (2)Sigma(g) (+) dressed states to generate vibrationally excited products.
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Affiliation(s)
- T W Schmidt
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
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Lee S, Luque J, Reppel J, Brown A, Crosley DR. Rotational energy transfer in NO (A 2Σ+,v′=0) by N2 and O2 at room temperature. J Chem Phys 2004; 121:1373-82. [PMID: 15260681 DOI: 10.1063/1.1756868] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
State-to-state rotational energy transfer (RET) rate coefficients for NO (A 2Sigma+, v'=0, J=5.5, 11.5, 17.5) were measured for N2 and O2 at room temperature using a pump-probe method. The NO A 2Sigma+ state is prepared by 226 nm light and the RET is monitored by fluorescence from the D 2Sigma+ v'=0 state, following excitation by a time-delayed laser at approximately 1.1 microm. Additionally, total collisional removal and final state distributions were measured exciting in the Q1+P21 band head, to simulate an NO laser-induced fluorescence atmospheric monitoring scheme. Time-resolved modeling is used to understand relaxation mechanisms and predict relaxation times in ambient air. H2O at atmospherically relevant concentrations does not affect the degree of RET in ambient air.
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Affiliation(s)
- Seonkyung Lee
- Molecular Physics Laboratory, SRI International, Menlo Park, California 94025, USA
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Kawai S, Fujimura Y, Kajimoto O, Takayanagi T. Exit interaction effect on nascent product state distribution of O(1D)+N2O-->NO+NO. J Chem Phys 2004; 120:6430-8. [PMID: 15267532 DOI: 10.1063/1.1649721] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have determined the rotational state distributions of NO(v'=0,1,2) products produced from the reaction O(1D)+N2O. This is the first full characterization of the product rotational distribution of this reaction. The main part of each rotational distribution (up to j' approximately 80) has rotational temperature approximately 20,000 K and all these distributions are quite near to those predicted by the phase space theory (PST). This observation and previously reported vibrational distribution indicate that the most part of the energy partitioning of the reaction products is at least apparently statistical although the intermediate of this reaction is not so stable as to ensure the long lifetime. On the other hand, the distributions in the high rotational levels (j'=80-100) are found to decrease more sharply as j' increases than the PST predictions. The origin of the observed decrease of the distribution is discussed with quasiclassical trajectory (QCT) calculations on a five-dimensional ab initio potential energy surface (PES). The observed near-statistical distribution and the sharp decrease in the high-j' levels are well reproduced by a "half-collision" QCT calculation, where statistical distribution at the reaction intermediate is assumed. This agreement shows the rotation-translation interaction in the exit region has an effect of yielding small high-j' populations. However, a little bias of the calculated distribution toward lower rotational excitation than the observed one indicates that the combination of the statistical intermediate and the exit interaction on the current PES does not completely describe the real system. It is suggested that the reaction intermediate is generated with the distribution which is close to statistical but a little biased toward yielding high-j' products, and that the interaction in the exit region of the PES results in the sharp decrease in the high-j' levels.
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Affiliation(s)
- Shinnosuke Kawai
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan
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Cheung ASC, Wong AL, Lo DHY, Leung KWS, Yoshino K, Thorne AP, Murray JE, Imajo T, Ito K, Matsui T. Application of a VUV Fourier transform spectrometer and synchrotron radiation source to measurements of. VI. The ε(0,0) band of NO. J Chem Phys 2003. [DOI: 10.1063/1.1611171] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Sun ZG, Liu HP, Lou NQ, Cong SL. Selecting ionization path by dynamic stark shift with strong laser pulse. Chem Phys Lett 2003. [DOI: 10.1016/s0009-2614(02)02033-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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47
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Luque J, Hudson EA, Booth JP, Petsalakis ID. Broadband absorption and ab initio results on the CF C 2Σ+–X 2Π system. J Chem Phys 2003. [DOI: 10.1063/1.1526637] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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Luque J, Hudson EA, Booth JP. CF A 2Σ+–X 2Π and B 2Δ–X 2Π study by broadband absorption spectroscopy in a plasma etch reactor: Determination of transition probabilities, CF X 2Π concentrations, and gas temperatures. J Chem Phys 2003. [DOI: 10.1063/1.1527923] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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49
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Cheung ASC, Lo DHY, Leung KWS, Yoshino K, Thorne AP, Murray JE, Ito K, Matsui T, Imajo T. The application of a vacuum ultraviolet Fourier transform spectrometer and synchrotron radiation source to measurements of: IV. The β(6,0) and γ(3,0) bands of NO. J Chem Phys 2002. [DOI: 10.1063/1.1421064] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Arusi-Parpar T, Heflinger D, Lavi R. Photodissociation followed by laser-induced fluorescence at atmospheric pressure and 24 degrees C: a unique scheme for remote detection of explosives. APPLIED OPTICS 2001; 40:6677-6681. [PMID: 18364979 DOI: 10.1364/ao.40.006677] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A unique scheme has been applied for sensitive remote detection of 2,4,6-trinitrotoluene (TNT) vapor trace amounts at atmospheric pressure and 24 degrees C. The detection concept is based on a single laser beam inducing a tandem process: photodissociation of TNT vapor followed by highly selective detection of its photofragments vibrationally excited NO, utilizing laser-induced fluorescence with the A2Sigma+(v' = 0) <-- X2Pi(v'' = 2) transition. A detection sensitivity of at least 8 parts in 10(9) of TNT vapor with a signal-to-noise ratio of approximately 10 has been experimentally verified for an unfocused approximately 5-mJ laser beam, measured at a distance of approximately 15 cm from the TNT sample.
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Affiliation(s)
- T Arusi-Parpar
- Non-Linear Optics Group, Electro-Optics Division, Soreq Nuclear Research Center, Yavne 81800, Israel
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