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Identification of absolute geometries of cis and trans molecular isomers by Coulomb Explosion Imaging. Sci Rep 2016; 6:38202. [PMID: 27910943 PMCID: PMC5133590 DOI: 10.1038/srep38202] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 11/04/2016] [Indexed: 01/13/2023] Open
Abstract
An experimental route to identify and separate geometric isomers by means of coincident Coulomb explosion imaging is presented, allowing isomer-resolved photoionization studies on isomerically mixed samples. We demonstrate the technique on cis/trans 1,2-dibromoethene (C2H2Br2). The momentum correlation between the bromine ions in a three-body fragmentation process induced by bromine 3d inner-shell photoionization is used to identify the cis and trans structures of the isomers. The experimentally determined momentum correlations and the isomer-resolved fragment-ion kinetic energies are matched closely by a classical Coulomb explosion model.
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Alagia M, Brunetti BG, Candori P, Falcinelli S, Moix Teixidor M, Pirani F, Richter R, Stranges S, Vecchiocattivi F. The double photoionization of hydrogen iodide molecules. J Chem Phys 2006; 124:204318. [PMID: 16774343 DOI: 10.1063/1.2201742] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The double photoionization of HI molecules has been investigated using vacuum ultraviolet synchrotron radiation in the energy range between 27 and 35 eV. The product ions have been detected by the use of time-of-flight mass spectrometry and the threshold energy for HI2+ and H+ + I+ formation has been determined. These results have been interpreted by the use of a theoretical model which has been previously applied by us to HBr2+ and HCl2+. On the basis of the reliability of such a model, an assessment of the systematic trends of the bond features along the HX2+ (X=F, Cl, Br, I) homologous series is given in this paper. In particular, the increase of the stability of these dications, in their lowest electronic states, when going towards the heavier molecules, has been rationalized considering the systematic variation of the charge transfer coupling between the H-X2+ and the H+-X+ states.
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Affiliation(s)
- M Alagia
- ISMN-CNR Sez. Roma 1, P.le A. Moro 5, 00185, Rome, Italy
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Bruna PJ, Grein F. Theoretical Studies on Dications and Trications of FH, ClH, and BrH. Properties of the Bound 15Σ- States. Electron-Spin g-Factors and Fine/Hyperfine Constants of the Metastable X3Σ- States of ClH2+ and BrH2+. J Phys Chem A 2006; 110:4906-17. [PMID: 16599461 DOI: 10.1021/jp0572838] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This theoretical study reports calculations on the fine and hyperfine structure parameters of the metastable X(3)Sigma(-)(sigma(2)pi(2)) state of ClH(2+) and BrH(2+). Data on the repulsive FH(2+) system are also included for comparison purposes. The hyperfine structure (hfs) coupling constants for magnetic (A(iso), A(dip)) and quadrupole (eQq) interactions are evaluated using B3LYP, MP4SDQ, CCSD, and QCISD methods and several basis sets. The fine structure (fs) constants (zero-field splitting lambda and spin-rotation coupling gamma) and electron-spin magnetic moments (g-factor) are evaluated in 2nd-order perturbation theory using multireference CI (MRCI) wave functions. Our calculations find for (35)Cl of ClH(2+) A(iso)/A(dip) = 110/-86 MHz; eQq(0) = -59 MHz; 2lambda = 20.4 cm(-1); g( perpendicular)(v = 0) = 2.02217; and gamma = -0.31 cm(-1) (to be compared with the available experimental A(iso)/A(dip)= 162/-30 MHz). For (79)BrH(2+), the corresponding values are 300/-400 MHz; 368 MHz; 362.6 cm(-1); 2.07302; and -0.98 cm(-1) (experimental 2lambda = 445(+/-80) cm(-1)). We find g( perpendicular)(ClH(2+)) to increase by about 0.0054 between v = 0 and 2, whereas the experimental effective g( perpendicular) changes drastically with vibrational excitation. Nuclear quadrupole coupling constants for halogen atoms X are found to be as large as corresponding A(dip)(X)'s, indicating that both terms may have to be included in the Hamiltonian used to interpret XH(2+) hyperfine spectra. A novel finding relates to the bound character of the 1(5)Sigma(-)(sigmapi(2)sigma) state in FH(2+), as already known for ClH(2+) and BrH(2+), but having a deeper potential well D(e) approximately 4,000 cm(-1) (versus 1,000 cm(-1) in the heavier radicals). Vertical ionization potentials for formation of XH(3+) trications are also discussed.
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Affiliation(s)
- Pablo J Bruna
- Department of Chemistry and Centre for Laser, Atomic and Molecular Sciences, University of New Brunswick, Fredericton, New Brunswick, Canada E3B 6E2
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Hu Z, Caló A, Nikkinen J, Matila T, Kukk E, Aksela H, Aksela S. Normal Auger spectra of Br in alkali bromide molecules. J Chem Phys 2004; 121:8246-52. [PMID: 15511144 DOI: 10.1063/1.1797732] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Molecular Auger electron spectra following the bromine 3d ionization in gas-phase alkali bromides and in HBr were studied both experimentally and theoretically. The AES for HBr and CsBr were measured using photoexcitation, and for LiBr, NaBr, and KBr by using electron impact. These results are compared with the theoretical spectra from nonrelativistic ab initio calculations and one-center approximation and with the spectra of Br(-), computed with the multiconfiguration Dirac-Fock method.
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Affiliation(s)
- Zhengfa Hu
- Department of Physical Sciences, University of Oulu, P.O. Box 3000, 90014 Oulu, Finland.
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Yencha AJ, Juarez AM, Pui Lee S, King GC, Bennett FR, Kemp F, McNab IR. Photo-double ionization of hydrogen iodide: experiment and theory. Chem Phys 2004. [DOI: 10.1016/j.chemphys.2004.05.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Alagia M, Brunetti BG, Candori P, Falcinelli S, Teixidor MM, Pirani F, Richter R, Stranges S, Vecchiocattivi F. Low-lying electronic states of HBr2+. J Chem Phys 2004; 120:6985-91. [PMID: 15267598 DOI: 10.1063/1.1669383] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The present study describes the characterization of energy and structure of HBr(2+) in its low-lying electronic states, achieved through an extension of a new empirical method [Chem. Phys. Lett. 379, 139 (2003)] recently introduced to evaluate the interatomic interaction in the HX(2+) (X=F,Cl,Br,I) molecular dications. The method is based on identification of the main components of the interaction and their evaluation through some simple correlation formulas. Potential energy curves, given in a simple, natural, and analytical form, made possible the calculations of some important properties, such as double-photoionization energy thresholds, vibrational spacing, average lifetime, and Franck-Condon factors. The predictions, compared with data available in the literature, are of great interest for the analysis and interpretation of some new experimental results.
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Alagia M, Brunetti BG, Candori P, Falcinelli S, Teixidor MM, Pirani F, Richter R, Stranges S, Vecchiocattivi F. Threshold-photoelectron-spectroscopy-coincidence study of the double photoionization of HBr. J Chem Phys 2004; 120:6980-4. [PMID: 15267597 DOI: 10.1063/1.1669382] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A threshold-photoelectron-coincidence spectrum of HBr has been recorded in the 32.2-35.8 eV photon energy range, with a resolution of approximately 0.01 eV, using a synchrotron radiation source. The X (3)Sigma(-) and a (1)Delta(2) states of the HBr(2+) dication are clearly observed in the spectrum, while there is no clear evidence for the formation of the b (1)Sigma(+) electronic state. For the first two states, the vibrational states v=0-3 have been resolved, while for the ground X (3)Sigma(-) state also spin-orbit splitting has been detected. The results appear in good agreement with previous experimental observations. A comparison with theoretical predictions indicates the role of "noncovalent" contributions to the interaction between the two atomic partners for the formation of metastable states.
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Yencha AJ, Juarez AM, Pui Lee S, King GC. Photo-double ionization of HBr and DBr studied by threshold photoelectrons coincidence spectroscopy. Chem Phys Lett 2003. [DOI: 10.1016/j.cplett.2003.10.048] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Alagia M, Boustimi M, Brunetti BG, Candori P, Falcinelli S, Richter R, Stranges S, Vecchiocattivi F. Mass spectrometric study of double photoionization of HBr molecules. J Chem Phys 2002. [DOI: 10.1063/1.1485066] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Hu YF, Bancroft GM, Tan KH. Variable-energy photoelectron spectroscopy of substituted rhenium and manganese pentacarbonyls: molecular orbital assignments and the interatomic resonant effect. Inorg Chem 2000; 39:1255-64. [PMID: 12526417 DOI: 10.1021/ic9912272] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
High-resolution variable-energy photoelectron spectra of M(CO)5X [M = Re, X = Re(CO)5, Cl, Br, and I; and M = Mn, X = Mn(CO)5 and Br] are reported. Tunable synchrotron radiation is used to distinguish the Re 5d and Br 4p orbital based peaks for the controversial Re(CO)5Br. Our results provide firm molecular orbital assignments for all of these molecules. The valence orbital in the ordering of ionization energies for M(CO)5Cl (M = Mn and Re) and Mn(CO)5Br is a 1(M-X) > e(X) > b2(M) > e(M); but for M(CO)5I (M = Mn and Re) and Re(CO)5Br the ordering is a1(M-X) > e(M) > b2(M) > e(X). The crossover of the HOMO in the Re molecules due to the change in the halogen electronegativities occurs at Re(CO)5Br. The metal np-->nd resonance is observed for all of these molecules. For molecules like M2(CO)10 (M = Re and Mn) and Mn(CO)5Br, the observation of this np-->nd resonance is useful in assigning the metal nd based orbitals in their valence level spectra. However, for molecules like Re(CO)5X (X = Br and Cl), a np-->nd type resonance is observed on bands arising from both Re 5d and halogen mp based orbitals. This new resonant effect on the ligand-based orbitals is shown to be mainly due to the interatomic resonant effect. The core and valence level chemical shifts of these compounds are treated using Jolly's approach to confirm the assignments for the valence level spectra of some of these molecules. The high-resolution inner valence and core level spectra of these compounds are reported. Broadening of Re 4f, Br 3d, and I 4d core level spectra is discussed. The Auger peaks are observed in the high-resolution, high-intensity Br 3d of Re(CO)5Br and I 4d of Re(CO)5I spectra.
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Affiliation(s)
- Y F Hu
- Department of Chemistry, University of Western Ontario, London, Ontario, Canada N6A 5B7
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Gelmukhanov F, gren H. X-ray resonant scattering involving dissociative states. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1996; 54:379-393. [PMID: 9913488 DOI: 10.1103/physreva.54.379] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Gel'mukhanov F, gren H, Svensson S, Aksela H, Aksela S. Theory of Auger spectra for molecular-field-split core levels. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1996; 53:1379-1387. [PMID: 9913027 DOI: 10.1103/physreva.53.1379] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Svensson S, Ausmees A, Osborne SJ, Bray G, Gel'mukhanov F, Ågren H, Sairanen O, Kivimäki A, Nõmmiste E, Aksela H, Aksela S. Observation of an anomalous decay ratio between the molecular field split levels in the S 2p core photoelectron and LVV Auger spectrum of H2S. PHYSICAL REVIEW LETTERS 1994; 72:3021-3024. [PMID: 10056047 DOI: 10.1103/physrevlett.72.3021] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Liu ZF, Bancroft GM, Tan KH, Schachter M. Molecular Auger resonance Raman effect: A high resolution study on the resonance Auger decay of HBr after the Br 3d-->5p pi Rydberg transition. PHYSICAL REVIEW LETTERS 1994; 72:621-624. [PMID: 10056481 DOI: 10.1103/physrevlett.72.621] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Correia N, Naves de Brito A, Keane MP, Karlsson L, Svensson S, Liegener C, Cesar A, Ågren H. Doubly charged valence states of formaldehyde, acetaldehyde, acetone, and formamide studied by means of photon excited Auger electron spectroscopy and ab initio calculations. J Chem Phys 1991. [DOI: 10.1063/1.461687] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Banichevich A, Peyerimhoff SD, Hess BA, van Hemert MC. Potential curves and predissociation rates for the heavy species HBr2+ and DBr2+. Chem Phys 1991. [DOI: 10.1016/0301-0104(91)80071-o] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Cesar A, Ågren H, Naves de Brito A, Svensson S, Karlsson L, Keane MP, Wannberg B, Baltzer P, Fournier PG, Fournier J. Vibronic and electronic states of doubly charged H2S studied by Auger and charge transfer spectroscopy and by ab initio calculations. J Chem Phys 1990. [DOI: 10.1063/1.459118] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Svensson S, Karlsson L, Baltzer P, Keane MP, Wannberg B. High-resolution Auger-electron spectrum of HCl and DCl. PHYSICAL REVIEW. A, GENERAL PHYSICS 1989; 40:4369-4377. [PMID: 9902678 DOI: 10.1103/physreva.40.4369] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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