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Stewart BA, Stephens TN, Lawrence BA, McBane GC. Rovibrational Energy Transfer in Ne−Li2(A1Σu+,v=0): Comparison of Experimental Data and Results from Classical and Quantum Calculations. J Phys Chem A 2010; 114:9875-85. [DOI: 10.1021/jp103504a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Brian A. Stewart
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, Department of Chemistry, Eastern Illinois University, Charleston, Illinois 61920, and Department of Chemistry, Grand Valley State University, Allendale, Michigan 49401
| | - Troy N. Stephens
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, Department of Chemistry, Eastern Illinois University, Charleston, Illinois 61920, and Department of Chemistry, Grand Valley State University, Allendale, Michigan 49401
| | - Barbara A. Lawrence
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, Department of Chemistry, Eastern Illinois University, Charleston, Illinois 61920, and Department of Chemistry, Grand Valley State University, Allendale, Michigan 49401
| | - George C. McBane
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, Department of Chemistry, Eastern Illinois University, Charleston, Illinois 61920, and Department of Chemistry, Grand Valley State University, Allendale, Michigan 49401
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Minaev B. Ab initio study of low-lying triplet states of the lithium dimer. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2005; 62:790-9. [PMID: 16099708 DOI: 10.1016/j.saa.2005.03.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2005] [Revised: 03/02/2005] [Accepted: 03/02/2005] [Indexed: 05/04/2023]
Abstract
Observation of Bose-Einstein condensation in Li27 initiated the interest in the scattering length of two ground state lithium atoms when they approach each other as a radical pair triplet aSigmau+3 state. But some properties of this state are still unknown. In present work, a number of low-lying triplet states of lithium molecule are calculated by multi-configuration self-consistent field (MCSCF) and response techniques with account of spin-orbit coupling, spin-spin coupling and some other magnetic perturbations. The singlet-triplet transition probabilities to the ground state are also presented. Most results are connected with the weakly bound lowest triplet a3Sigmau+ state, whose radiative lifetime and spin-splitting are unknown so far in spite of its great importance in Bose-Einstein condensation. Calculations indicate that this state has a very small spin-splitting, lambdass=-0.01 cm-1, which is negligible in comparison with the line-width in experimental Fourier transform spectra published so far. Similar splitting is obtained for the upper state of the 1(3)Sigmag+--a3Sigmau+ transition. This is in agreement with experimental rovibronic analysis of the 1(3)Sigmag+--a3Sigmau+ band system in which the triplet structure was not resolved. The radiative lifetime of the a3Sigmau+ state is predicted to exceed 10 h.
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Affiliation(s)
- Boris Minaev
- State University of Technology, Cherkassy 18006, Ukraine.
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Burns P, Wilkins AD, Hickman AP, Huennekens J. The NaK 1(b) 3Pi(Omega=0) state hyperfine structure and the 1(b) 3Pi(Omega=0) approximately 2(A) 1Sigma+ spin-orbit interaction. J Chem Phys 2005; 122:074306. [PMID: 15743231 DOI: 10.1063/1.1844293] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
We have measured the hyperfine structure of mutually perturbing rovibrational levels of the 1(b) 3Pi0 and 2(A) 1Sigma+ states of the NaK molecule, using the perturbation-facilitated optical-optical double resonance method with copropagating lasers. The unperturbed 1(b) 3Pi0 levels are split into four hyperfine components by the Fermi contact interaction bFIS. Mixing between the 1(b) 3Pi0 and 2(A) 1Sigma+ levels imparts hyperfine structure to the nominally singlet component of the perturbed levels and reduces the hyperfine splitting of the nominally triplet component. Theoretical analysis relates these observations to the hyperfine splitting that each 1(b) 3Pi0 level would have if it were not perturbed by a 2(A) 1Sigma+ level. Using this analysis, we demonstrate that significant hyperfine splitting arises because the 1(b) 3Pi0 state cannot be described as pure Hund's case (a). We determine bF for the 1(b) 3Pi0 levels and also a more accurate value for the magnitude of the singlet-triplet spin-orbit coupling HSO=[1(b) 3Pi0(vb,J)(H(SO))2(A) 1Sigma+(vA,J). Using the known spectroscopic constants of the 1(b) 3Pi state, we obtain bF=0.009 89+/-0.000 27 cm(-1). The values of (H(SO)) are found to be between 2 and 3 cm(-1), depending on vb, vA, and J. Dividing (H(SO)) by calculated vibrational overlap integrals, and taking account of the 1(b) 3Pi(Omega) rotational mixing, we can determine the magnitude of the electronic part H(el) of H(SO). Our results yield (H(el))=(16.33+/-0.15) cm(-1), consistent with our previous determinations using different techniques.
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Affiliation(s)
- P Burns
- Department of Physics, Lehigh University, 16 Memorial Drive East, Bethlehem, Pennsylvania 18015, USA
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Lazarov G, Lyyra AM, Li L. Enhanced Access to the Dark Triplet States of (7)Li(2) through New Singlet-Triplet A(1)Sigma(+)(u) approximately b(3)Pi(u) Perturbation Window Levels: Perturbation-Facilitated Optical-Optical Double Resonance Study of the 2(3)Sigma(+)(g) State. JOURNAL OF MOLECULAR SPECTROSCOPY 2001; 205:73-80. [PMID: 11148109 DOI: 10.1006/jmsp.2000.8238] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Two new pairs of singlet-triplet A(1)Sigma(+)(u) approximately b(3)Pi(u) mixed levels of (7)Li(2) have been observed and used here as "window" levels in cw perturbation-facilitated optical-optical double-resonance (PFOODR) experiments. Previously, only one b(3)Pi(u) vibrational level, v = 19, was known to mix with the singlet A(1)Sigma(+)(u) v = 13 level, resulting in three perturbed A approximately b pairs [L. Li, T. An, T.-J. Whang, A. M. Lyyra, W. C. Stwalley, R. W. Field, and R. A. Bernheim, J. Chem. Phys. 96, 3342 (1992)]. The scarcity of window levels and the resulting difficulty in accessing the dark triplet states of Li(2) is caused by the weak spin-orbit interaction of Li(2). The two new mixed b(3)Pi(u) v = 15 and 22 levels reported here enhance access to the dark triplet state manifold through expansion of the Franck-Condon overlap factor range. Furthermore, the earlier range of accessible rotational levels, N = 5, 7, and 10, is now expanded to include N = 8 and N = 16, thereby allowing for more reliable determination of the excited triplet states rotational structure. To demonstrate the importance of the new A(1)Sigma(+)(u) approximately b(3)Pi(u) mixed levels, we have studied the 2(3)Sigma(+)(g) state by cw PFOODR fluorescence excitation spectroscopy. New molecular constants and RKR potential curve have been determined. As previously reported [L. Li, G. Lazarov, and A. M. Lyyra, J. Mol. Spectrosc. 191, 387 (1998)], the 2(3)Sigma(+)(g) state interacts with the repulsive 1(3)Pi(g) state by L-uncoupling and predissociates. We show that some 2(3)Pi(g) levels predissociate accidentally by the 1(3)Pi(g) state via the 2(3)Sigma(+)(g) state through L-uncoupling. Copyright 2001 Academic Press.
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Affiliation(s)
- G Lazarov
- Department of Physics, Temple University, Philadelphia, Pennsylvania, 19122
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Li L, Dai X, Liu Y, Clevenger JO, Field RW, Jeung GH, Geum N, Lyyra AM. The Predissociation of the 1(3)Sigma(-)(g) State of (7)Li(2). JOURNAL OF MOLECULAR SPECTROSCOPY 2001; 205:139-145. [PMID: 11148118 DOI: 10.1006/jmsp.2000.8247] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The predissociation of the 1(3)Sigma(-)(g) v >/= 10 levels of (7)Li(2) has been observed by pulsed and continuous-wave perturbation-facilitated optical-optical double-resonance spectroscopy (PFOODR). Our ab initio calculation shows that the inner wall of the 1(3)Sigma(-)(g) potential intersects the 1(3)Pi(g) repulsive potential at internuclear distance R = 2.00 Å. The predissociation is due to a DeltaS = 0, DeltaLambda = +/-1 rotational-electronic interaction with the repulsive 1(3)Pi(g) state. Copyright 2001 Academic Press.
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Affiliation(s)
- L Li
- Department of Physics, Tsinghua University, Beijing, 100084, China
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Stewart B, Magill PD, Pritchard DE. Quasi-Resonant Vibration−Rotation Transfer in Inelastic Li2*−Ne Collisions. J Phys Chem A 2000. [DOI: 10.1021/jp001445c] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Brian Stewart
- Department of Physics, Wesleyan University, Middletown, Connecticut 06549
| | | | - David E. Pritchard
- Department of Physics and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
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Chen H, Li L, Lazarov G, Wang X, Lyyra AM, Huennekens J, Field RW. Rotational Pattern Difference in Resolved Fluorescence Spectra with Different Detection Schemes. JOURNAL OF MOLECULAR SPECTROSCOPY 1999; 196:197-211. [PMID: 10409450 DOI: 10.1006/jmsp.1999.7873] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The relative intensities of rotational lines in resolved fluorescence spectra are dependent on the detection direction and the choice of the detection scheme when a grating monochromator is used. These differences arise from the spatially anisotropic distribution of the fluorescence, the rotational branch dependence of the fluorescence polarization, and the polarization dependence of the monochromator grating efficiency. Both the anisotropy of the emission and the rotational branch dependence of the fluorescence polarization are enhanced in double-resonance excitation schemes. In the present work, we analyze the relative intensities in the (7)Li(2) 1(3)Sigma(-)(g) --> 1(b)(3)Pi(u) and 1(3)Delta(g) --> 1(b)(3)Pi(u) resolved fluorescence spectra, observed following double-resonance excitation, for three different detection schemes. Copyright 1999 Academic Press.
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Affiliation(s)
- H Chen
- Department of Physics, Tsinghua University, Beijing, 100084, China
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Kokoouline V, Dulieu O, Kosloff R, Masnou-Seeuws F. Mapped Fourier methods for long-range molecules: Application to perturbations in the Rb2(0u+) photoassociation spectrum. J Chem Phys 1999. [DOI: 10.1063/1.478860] [Citation(s) in RCA: 202] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Williams RM, Papanikolas JM, Rathje J, Leone SR. Compositional control of rovibrational wave packets in the E(1Σg+) “shelf” state of Li2 via quantum-state-resolved intermediate state selection. J Chem Phys 1997. [DOI: 10.1063/1.473894] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Affiliation(s)
- Richard M. Williams
- JILA, National Institute of Standards and Technology and University of Colorado, Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0440
| | - John M. Papanikolas
- JILA, National Institute of Standards and Technology and University of Colorado, Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0440
| | - Jacob Rathje
- JILA, National Institute of Standards and Technology and University of Colorado, Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0440
| | - Stephen R. Leone
- JILA, National Institute of Standards and Technology and University of Colorado, Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0440
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Li L, Yiannopoulou A, Urbanski K, Lyyra AM, Ji B, Stwalley WC, An T. Hyperfine structures of the 7Li2 b3Πu, 23Πg, and 33Πg states: Continuous wave perturbation facilitated optical–optical double resonance spectroscopy. J Chem Phys 1996. [DOI: 10.1063/1.473003] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
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Gao Y, Gorgone PS, Davis S, McCall EK, Stewart B. Dependence of level‐resolved energy transfer on initial vibrational level in Li2A1Σu+−Ne collisions. J Chem Phys 1996. [DOI: 10.1063/1.470908] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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13
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Weyh T, Ahmed K, Demtröder W. Radiative lifetimes, quenching cross sections and population mechanisms of the C1Πu, 23Πg and 1 3Δg states of 7Li2. Chem Phys Lett 1996. [DOI: 10.1016/0009-2614(95)01326-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Yiannopoulou A, Urbanski K, Antonova S, Lyyra AM, Li L, An T, Whang TJ, Ji B, Wang XT, Stwalley WC, Leininger T, Jeung G. The 2 3Πg and 3 3Πg states of 7Li2: Optical–optical double resonance spectroscopy and ab initio calculations. J Chem Phys 1995. [DOI: 10.1063/1.470469] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
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Yiannopoulou A, Urbanski K, Lyyra AM, Li L, Ji B, Bahns JT, Stwalley WC. Perturbation facilitated optical–optical double resonance spectroscopy of the 2 3Σ+g, 3 3Σ+g, and 4 3Σ+gRydberg states of7Li2. J Chem Phys 1995. [DOI: 10.1063/1.468612] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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Yiannopoulou A, Ji B, Li L, Li M, Urbanski K, Lyyra AM, Stwalley WC, Jeung G. The doubly excited 1 3Σ−g state of 7Li2. J Chem Phys 1994. [DOI: 10.1063/1.467543] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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He C, Gold LP, Faust CM, Le L, Bernheim RA. Anomalous nuclear spin effects in the laser induced fluorescence from the A 1Σ u+ state of 6Li 2. J Chem Phys 1992. [DOI: 10.1063/1.463880] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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18
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Li L, An T, Whang T, Lyyra AM, Stwalley WC, Field RW, Bernheim RA. Hyperfine splitting of the 1 3Δg Rydberg state of 7Li2. J Chem Phys 1992. [DOI: 10.1063/1.461930] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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19
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Jeng W, Xie X, Gold LP, Bernheim RA. Fine structure and Zeeman effect in theb(1)3Πustate of6Li2by Doppler‐free polarization spectroscopy. J Chem Phys 1991. [DOI: 10.1063/1.459983] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Jeng WH, Xie X, Gold LP, Bernheim RA. Faraday rotation of a A 1∑+u–X 1∑+g transition in 6Li2. J Chem Phys 1990. [DOI: 10.1063/1.458881] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Bahns JT, Stwalley WC, Pichler G. The 458 nm diffuse band of the lithium dimer. J Chem Phys 1989. [DOI: 10.1063/1.455936] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Dissociation Dynamics of Polyatomic Molecules. ACTA ACUST UNITED AC 1989. [DOI: 10.1016/s0065-2199(08)60096-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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23
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Huennekens J, Loza A, Masters M, Sando KM. Near‐infrared bound–free emission from the NaK molecule. J Chem Phys 1988. [DOI: 10.1063/1.454493] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Schmidt I, Meyer W, Krüger B, Engelke F. A theoretical and experimental investigation of the predissociative line shifts of the b 3Πu state of Li2. Chem Phys Lett 1988. [DOI: 10.1016/0009-2614(88)87046-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Schmidt-Mink I, Meyer W. Predissociation lifetimes of the b3Πu state of Li2 and the accidental predissociation of its A1Σu+ state. Chem Phys Lett 1985. [DOI: 10.1016/0009-2614(85)87153-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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28
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Xie X, Field RW. The 6Liz A1Σu+ ∼ b3Πu spin—orbit perturbations: Sub-Doppler spectra and steady state kinetic lineshape model. Chem Phys 1985. [DOI: 10.1016/0301-0104(85)80130-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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