1
|
Dunning TH, Xu LT. Electronic structure of Li 1,2,3 +,0,- and nature of the bonding in Li 2,3 +,0,. J Comput Chem 2024; 45:405-418. [PMID: 37966878 DOI: 10.1002/jcc.27246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 10/11/2023] [Accepted: 10/13/2023] [Indexed: 11/16/2023]
Abstract
The current study of the small lithium molecules Li2 +,0,- and Li3 +,0,- focuses on the nature of the bonding in these molecules as well as their structures and energetics (bond energies, ionization energies, and electron affinities). Valence CASSCF (2s,2p) calculations incorporate nondynamical electron correlation in the calculations, while the corresponding multireference configuration interaction and coupled cluster calculations incorporate dynamical electron correlation. Treatment of nondynamical correlation is critical for properly describing the Li2,3 +,0,- molecules as well as the Li- anion with dynamical correlation, in general, only fine-tuning the predictions. All lithium molecules and ions are bound, with the Li3 + and Li2 + ions being the most strongly bound, followed by Li3 - , Li2 , Li2 - and Li3 . The minimum energy structures of Li3 +,0,- are, respectively, an equilateral triangle, an isosceles triangle, and a linear structure. The results of SCGVB calculations are analyzed to obtain insights into the nature of the bonding in these molecules. An important finding of this work is that interstitial orbitals, a concept first put forward by McAdon and Goddard in 1985, play an essential role in the bonding of all lithium molecules considered here except for Li2 . The interstitial orbitals found in the Li3 +,0 molecules likely give rise to the non-nuclear attractors/maxima observed in these molecules.
Collapse
Affiliation(s)
- Thom H Dunning
- Department of Chemistry, University of Washington, Seattle, Washington, USA
| | - Lu T Xu
- Department of Chemistry, University of Washington, Seattle, Washington, USA
| |
Collapse
|
2
|
Nakatsuji H, Nakashima H. Potential curves of the lower nine states of Li2 molecule: Accurate calculations with the free complement theory and the comparisons with the SAC/SAC-CI results. J Chem Phys 2022; 157:094109. [DOI: 10.1063/5.0101315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The free-complement (FC) theory proposed for solving the Schrödinger equation of atoms and molecules highly accurately was applied to the calculations of the potential curves of the lower nine states of the Li2 molecule. The results were compared with the accurate experimental Rydberg-Klein-Rees (RKR) potential curves available. They overlap completely with each other without any shift everywhere for all the states of Li2. At all the calculated points on the seven potential curves ranging between -14.83 ~ -15.00 hartree, the average difference was only 0.0583 kcal/mol and the maximum difference was only +0.165 kcal/mol. For the vertical excitation energies from the ground state curve to the seven excited states, the differences between theory and experiment were 0.000645 eV in average and their maximum difference was -0.00720 eV. The potential properties calculated with the FC theory also agreed well with the experimental values. These results show a high potentiality of the FC theory as a highly predictive quantum chemistry theory. For comparison, as an example of the Hartree-Fock based theory popular in modern quantum chemistry, we adopted the SAC-CI theory using a highly flexible basis set. While the FC theory gave the absolute agreements with experiments, the SAC-CI potential curves compare reasonably well with experiments only after shifting-down of the SAC-CI curves by 5.727 kcal/mol. The differences of the excitation energies between SAC-CI and experiments were 0.00428 eV in average and the maximum difference was +0.10967 eV. The SAC-CI results reported in 1985 were less accurate but still reasonable.
Collapse
Affiliation(s)
- Hiroshi Nakatsuji
- Quantum Chemistry Research Institute, Quantum Chemistry Research Institute, Japan
| | | |
Collapse
|
3
|
Fanthorpe J, Gao Y, Stewart B. Rotational Energy Transfer in Highly Excited States of Lithium Dimer: Experiment and Modeling. J Phys Chem A 2020; 124:7373-7379. [PMID: 32835478 DOI: 10.1021/acs.jpca.0c04960] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report level-resolved rate coefficients for collision-induced rotational energy transfer in the 7Li2*-Ne system, with 7Li2* in the highly electronically excited E(3)1Σg+(vi = 4, ji = 31) and F(4)1Σg+(vi = 10, ji = 31) states. The distributions of rate coefficients are strikingly different from those previously measured for the A(1)1Σu+(vi = 2-24, ji = 30) state of the same molecule, falling off much more rapidly with increasing rotational quantum number change |Δj|. The reason for the difference was explored by means of an inverse Monte Carlo approach employing classical trajectories and a model potential, which was adjusted to give agreement with experiment. The modeling strongly suggests that the E and F state interaction potentials are much more nearly isotropic than that of the A state. The resulting dramatic reduction in rate coefficient, especially for large |Δj|, may be relevant in the relaxation of gases at high temperatures.
Collapse
Affiliation(s)
- Jacob Fanthorpe
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, United States
| | - Yunxiao Gao
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, United States
| | - Brian Stewart
- Department of Physics, Wesleyan University, Middletown, Connecticut 06459, United States
| |
Collapse
|
4
|
Sanli A, Pan X, Magnier S, Huennekens J, Lyyra AM, Ahmed EH. Measurement of the Na251Σg+→A1Σu+ and 61Σg+→A1Σu+ transition dipole moments using optical-optical double resonance and Autler–Townes spectroscopy. J Chem Phys 2017; 147:204301. [DOI: 10.1063/1.5002726] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
- Aydin Sanli
- Physics Department, Temple University, Philadelphia, Pennsylvania 19122, USA
| | - Xinhua Pan
- Physics Department, Temple University, Philadelphia, Pennsylvania 19122, USA
| | - Sylvie Magnier
- Université Lille, CNRS, UMR8523-PhLAM-Laboratoire de Physique des Lasers, Atomes et Molecules, F-59000 Lille, France
| | - John Huennekens
- Department of Physics, Lehigh University, 16 Memorial Drive East, Bethlehem, Pennsylvania 18015, USA
| | - A. Marjatta Lyyra
- Physics Department, Temple University, Philadelphia, Pennsylvania 19122, USA
| | - Ergin H. Ahmed
- Physics Department, Temple University, Philadelphia, Pennsylvania 19122, USA
| |
Collapse
|
5
|
Pazyuk EA, Zaitsevskii AV, Stolyarov AV, Tamanis M, Ferber R. Laser synthesis of ultracold alkali metal dimers: optimization and control. RUSSIAN CHEMICAL REVIEWS 2015. [DOI: 10.1070/rcr4534] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
6
|
Musiał M, Kucharski SA. First Principle Calculations of the Potential Energy Curves for Electronic States of the Lithium Dimer. J Chem Theory Comput 2014; 10:1200-11. [DOI: 10.1021/ct401076e] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Monika Musiał
- Institute of Chemistry, University of Silesia, Szkolna 9, 40-006 Katowice, Poland
| | | |
Collapse
|
7
|
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
| |
Collapse
|
8
|
Le Roy RJ, Dattani NS, Coxon JA, Ross AJ, Crozet P, Linton C. Accurate analytic potentials for Li2(X Σ1g+) and Li2(A Σ1u+) from 2 to 90 Å, and the radiative lifetime of Li(2p). J Chem Phys 2009; 131:204309. [DOI: 10.1063/1.3264688] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
|
9
|
Salihoglu O, Qi P, Ahmed EH, Kotochigova S, Magnier S, Lyyra AM. Comparison of Autler–Townes splitting based absolute measurements of the L7i2 A Σ1u+−X Σ1g+ electronic transition dipole moment with ab initio theory. J Chem Phys 2008; 129:174301. [DOI: 10.1063/1.3000416] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
|
10
|
Qi P, Bai J, Ahmed E, Lyyra AM, Kotochigova S, Ross AJ, Effantin C, Zalicki P, Vigué J, Chawla G, Field RW, Whang TJ, Stwalley WC, Knöckel H, Tiemann E, Shang J, Li L, Bergeman T. New spectroscopic data, spin-orbit functions, and global analysis of data on the AΣu+1 and bΠu3 states of Na2. J Chem Phys 2007; 127:044301. [PMID: 17672684 DOI: 10.1063/1.2747595] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The lowest electronically excited states of Na2 are of interest as intermediaries in the excitation of higher states and in the development of methods for producing cold molecules. We have compiled previously obtained spectroscopic data on the A 1Sigmau+ and b 3Piu states of Na2 from about 20 sources, both published and unpublished, together with new sub-Doppler linewidth measurements of about 15,000 A<--X transitions using polarization spectroscopy. We also present new ab initio results for the diagonal and off-diagonal spin-orbit functions. The discrete variable representation is used in conjunction with Hund's case a potentials plus spin-orbit effects to model data extending from v=0 to very close to the 3 2S+3 2P12 limit. Empirical estimates of the spin-orbit functions agree well with the ab initio functions for the accessible values of R. The potential function for the A state includes an exchange potential for S+P atoms, with a fitted coefficient somewhat larger than the predicted value. Observed and calculated term values are presented in an auxiliary (EPAPS) file as a database for future studies on Na2.
Collapse
Affiliation(s)
- P Qi
- Physics Department, Temple University, Philadelphia, Pennsylvania 19122-6082, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Lee SY, Boo BH, Kang HK, Kang D, Judai K, Nishijo J, Nishi N. Reexamination of the structures and energies of Li2C2 and Li4C4. Chem Phys Lett 2005. [DOI: 10.1016/j.cplett.2005.05.123] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
12
|
Tamanis M, Ferber R, Zaitsevskii A, Pazyuk EA, Stolyarov AV, Chen H, Qi J, Wang H, Stwalley WC. High resolution spectroscopy and channel-coupling treatment of the A 1Σ+–b 3Π complex of NaRb. J Chem Phys 2002. [DOI: 10.1063/1.1505442] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
13
|
Stauffer HU, Ballard JB, Amitay Z, Leone SR. Simultaneous phase control of Li2 wave packets in two electronic states. J Chem Phys 2002. [DOI: 10.1063/1.1427708] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
|
14
|
|
15
|
|
16
|
Bouloufa N, Cacciani P, Vetter R, Yiannopoulou A, Martin F, Ross AJ. A full description of the potential curve of the B 1Πu state of 7Li2. J Chem Phys 2001. [DOI: 10.1063/1.1364687] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
17
|
Antonova S, Lazarov G, Urbanski K, Lyyra AM, Li L, Jeung GH, Stwalley WC. Predissociation of the F(4) 1Σg+ state of Li2. J Chem Phys 2000. [DOI: 10.1063/1.481335] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
18
|
|
19
|
Stwalley WC, Wang H. Photoassociation of Ultracold Atoms: A New Spectroscopic Technique. JOURNAL OF MOLECULAR SPECTROSCOPY 1999; 195:194-228. [PMID: 10329265 DOI: 10.1006/jmsp.1999.7838] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The new spectroscopic technique of photoassociation of ultracold atoms is reviewed, with an emphasis on connecting this area to traditional bound-state molecular spectroscopy. In particular, in contrast to photoassociative spectra at thermal energies, which are broad and of low information content, photoassociative spectra of ultracold atoms are high resolution, permitting observation of small vibrational and rotational spacings of long-range molecular levels near dissociation (typically with outer classical turning points >20 Å). The types of detection and theoretical analysis employed are illustrated, primarily using the example of 39K2. Future directions and applications of this field (e.g., to ultracold molecular formation) are also discussed. Copyright 1999 Academic Press.
Collapse
Affiliation(s)
- WC Stwalley
- Department of Physics, University of Connecticut, 2152 Hillside Road, Storrs, Connecticut, 06269-3046
| | | |
Collapse
|
20
|
Gutterres R, Argollo de Menezes M, Fellows C, Dulieu O. Generalized simulated annealing method in the analysis of atom–atom interaction. Chem Phys Lett 1999. [DOI: 10.1016/s0009-2614(98)01243-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
21
|
Wang X, Yang J, Qi J, Lyyra AM. Precise Molecular Constants for the 6Li2 A1Sigma+u-X1Sigma+g System by Sub-Doppler Polarization Spectroscopy. JOURNAL OF MOLECULAR SPECTROSCOPY 1998; 191:295-305. [PMID: 9753564 DOI: 10.1006/jmsp.1998.7645] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We report here new and more accurate molecular constants from sub-Doppler polarization spectroscopy of the A1Sigma+u-X1Sigma+g system of 6Li2 using single mode cw dye lasers. These new constants cover the range of vibrational levels from v" = 0-8 in the ground state and v' = 0-24 in the excited state. New molecular constants and RKR potential energy curves for the A1Sigma+u and X1Sigma+g states are given. The Te value for the A1Sigma+u state is 14068.043(34) cm-1. The analysis indicates that there is a noticeable breakdown of the Born-Oppenheimer approximation for the 6Li2 and 7Li2 isotopomers. Copyright 1998 Academic Press.
Collapse
Affiliation(s)
- X Wang
- Physics Department, Temple University, Philadelphia, Pennsylvania, 19122
| | | | | | | |
Collapse
|
22
|
Lee AR, Kalotas TM, Adams NA. Modified Morse Potential for Diatomic Molecules. JOURNAL OF MOLECULAR SPECTROSCOPY 1998; 191:137-141. [PMID: 9724589 DOI: 10.1006/jmsp.1998.7629] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We present a diatomic potential which closely resembles the standard Morse function but incorporates additional flexibility for fitting experimental vibrational energy-gap data. This flexibility is accommodated by introducing a continuously variable radially dependent change in the exponent of the Morse function, which in practice is adequately realized via a relatively small number of constant parameters. As an illustration, the method is applied to calculate the quantum vibrational levels of the X1Sigma+<INF POS="STACK">g ground electronic state of the N2 molecule. Copyright 1998 Academic Press.
Collapse
Affiliation(s)
- AR Lee
- Physics Department, La Trobe University, Bundoora, Victoria, 3083, Australia
| | | | | |
Collapse
|
23
|
Urbanski K, Antonova S, Lyyra AM, Li L, Ji B. The G 1Πg state of 7Li2 revisited: Observation and analysis of high vibrational levels. J Chem Phys 1998. [DOI: 10.1063/1.476632] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- K. Urbanski
- Department of Physics, Temple University, Philadelphia, Pennsylvania 19122
| | - S. Antonova
- Department of Physics, Temple University, Philadelphia, Pennsylvania 19122
| | - A. M. Lyyra
- Department of Physics, Temple University, Philadelphia, Pennsylvania 19122
| | - Li Li
- Department of Modern Applied Physics, Tsinghua University, Beijing 10084, China
| | - B. Ji
- Department of Physics U46, University of Connecticut, 2152 Hillside Rd., Storrs, Connecticut 06269
| |
Collapse
|
24
|
Antonova S, Urbanski K, Lyyra A, Spano F, Li L. State to state collision energy transfer in singlet states of Li2. Chem Phys Lett 1997. [DOI: 10.1016/s0009-2614(97)00071-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|