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Prosmiti R, González-Lezana T. Computational Modeling: Up-to-Date Approaches and Cutting-Edge Applications from Clusters, Nanostructures to Bulk Systems. Chemphyschem 2024; 25:e202400207. [PMID: 38837591 DOI: 10.1002/cphc.202400207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Indexed: 06/07/2024]
Abstract
The contributions in this special theme collection, in honor to Prof. P. Villarreal, cover a broad variety of computational methodologies and experimental techniques, containing studies on gas phase, clusters and condensed phase systems.
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Affiliation(s)
- Rita Prosmiti
- Instituto de Fìsica Fundamental, IFF-CSIC, Serrano 123, 28006, Madrid, Spain
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2
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Seikh L, Dhara S, Singh AK, Singh A, Dey S, Indra A, Lahiri GK. The isomer-sensitive electrochemical HER of ruthenium(II)-hydrido complexes involving redox-active azoheteroaromatics. Dalton Trans 2024; 53:1746-1756. [PMID: 38168794 DOI: 10.1039/d3dt02925e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
The article deals with the development of isomeric ruthenium(II)-hydrido complexes [RuII(H)(L1)(PPh3)2(CO)]ClO4 ([1a]ClO4-[1b]ClO4)/[RuII(H)(L2)(PPh3)2(CO)]ClO4 ([2a]ClO4-[2b]ClO4) involving azo coupled L1 [L1: (E)-1,2-bis(1-methyl-1H-pyrazol-3-yl)diazene]/L2 [L2: (E)-1,2-bis(4-iodo-1-methyl-1H-pyrazol-3-yl)diazene], respectively. Structural evaluation of the complexes affirmed the syn conformation of the coordinated/uncoordinated pyrazole groups of L and its unperturbed neutral azo (NN) state. Isomeric forms in [1a]ClO4/[1b]ClO4 or [2a]ClO4/[2b]ClO4 differed with respect to the cis and trans orientations of the coordinated CO and N(azo) donor of L, respectively. It also demonstrated the formation of intermolecular hydrogen-bonded dimeric or 1D-polymeric chains in [1a]ClO4/[2b]ClO4 or [1b]ClO4, respectively. Successive two-electron reductions of the complexes varied to an appreciable extent as a function of the heterocycles connected to L. The involvement of the azo function of L towards the reductions ([NN]0 → [NN]˙- → [NN]2-) was supported by the DFT calculated MOs and Mulliken spin density at the paramagnetic state, which was further validated by the radical EPR profile of the first reduced (S = 1/2) state. Isomeric [1a]ClO4/[1b]ClO4 or [2a]ClO4/[2b]ClO4 immobilised on the carbon cloth support underwent various electrochemical acidic HERs (hydrogen evolution reactions) with TOF/10-1 s-1: [1a]ClO4 (0.83) > [1b]ClO4 (0.68) > [2a]ClO4 (0.50) > [2b]ClO4 (0.37).
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Affiliation(s)
- Liton Seikh
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India.
| | - Suman Dhara
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India.
| | - Ajit Kumar Singh
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh-221005, India.
| | - Aditi Singh
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India.
| | - Sanchaita Dey
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India.
| | - Arindam Indra
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh-221005, India.
| | - Goutam Kumar Lahiri
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India.
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3
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Nabi R, Staab JK, Mattioni A, Kragskow JGC, Reta D, Skelton JM, Chilton NF. Accurate and Efficient Spin-Phonon Coupling and Spin Dynamics Calculations for Molecular Solids. J Am Chem Soc 2023; 145. [PMID: 37917936 PMCID: PMC10655086 DOI: 10.1021/jacs.3c06015] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 10/16/2023] [Accepted: 10/18/2023] [Indexed: 11/04/2023]
Abstract
Molecular materials are poised to play a significant role in the development of future optoelectronic and quantum technologies. A crucial aspect of these areas is the role of spin-phonon coupling and how it facilitates energy transfer processes such as intersystem crossing, quantum decoherence, and magnetic relaxation. Thus, it is of significant interest to be able to accurately calculate the molecular spin-phonon coupling and spin dynamics in the condensed phase. Here, we demonstrate the maturity of ab initio methods for calculating spin-phonon coupling by performing a case study on a single-molecule magnet and showing quantitative agreement with the experiment, allowing us to explore the underlying origins of its spin dynamics. This feat is achieved by leveraging our recent developments in analytic spin-phonon coupling calculations in conjunction with a new method for including the infinite electrostatic potential in the calculations. Furthermore, we make the first ab initio determination of phonon lifetimes and line widths for a molecular magnet to prove that the commonplace Born-Markov assumption for the spin dynamics is valid, but such "exact" phonon line widths are not essential to obtain accurate magnetic relaxation rates. Calculations using this approach are facilitated by the open-source packages we have developed, enabling cost-effective and accurate spin-phonon coupling calculations on molecular solids.
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Affiliation(s)
- Rizwan Nabi
- Department
of Chemistry, University of Manchester, Manchester M13 9PL, U.K.
| | - Jakob K. Staab
- Department
of Chemistry, University of Manchester, Manchester M13 9PL, U.K.
| | - Andrea Mattioni
- Department
of Chemistry, University of Manchester, Manchester M13 9PL, U.K.
| | - Jon G. C. Kragskow
- Department
of Chemistry, University of Manchester, Manchester M13 9PL, U.K.
- Department
of Chemistry, University of Bath, Bath BA2 7AY, U.K.
| | - Daniel Reta
- Department
of Chemistry, University of Manchester, Manchester M13 9PL, U.K.
- Faculty
of Chemistry, University of the Basque Country
UPV/EHU, 20018 Donostia, Spain
- Donostia
International Physics Center (DIPC), 20018 Donostia, Spain
- IKERBASQUE,
Basque Foundation for Science, 48013 Bilbao, Spain
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4
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Vilà A, González M. Quantum dynamics of the Br 2 (B-excited state) photodissociation in superfluid helium nanodroplets: importance of the recombination process. Phys Chem Chem Phys 2022; 24:24353-24361. [PMID: 36178095 DOI: 10.1039/d2cp02984g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have studied the Br2 photodissociation dynamics (B ← X electronic transition) of Br2(v = 0, X)@(4He)N doped nanodroplets (T = 0.37 K) at zero angular momentum, with N in the 100-1000 interval. To do this, we have used a quantum mechanical hybrid strategy proposed by us and, as far as we know, this is the second quantum dynamics study available on the photodissociation of molecules in superfluid helium nanodroplets. While the results obtained for some properties are qualitatively similar to those reported previously by us for the Cl2(B ← X) related case (in particular, the oscillating Br final velocity distribution which also arises from quantum interferences), large differences are evident in three key properties: the photodissociation mechanism and probability and the time scale of the process. This can be interpreted on the basis of the significantly lower excitation energy achieved by the Br2(B ← X) transition and the higher reduced mass of Br-Br in comparison to the chlorine case. The Br2(B) photodissociation dynamics is significantly more complex than that of Cl2(B) and leads to the fragmentation of the initial wave packet. Thus, the probability of non-dissociation is equal to 17, 18, 51, 85 and 100% for N = 100, 200, 300, 500 and 1000, respectively, while for chlorine this probability is equal to zero. In spite of the very large experimental difficulties that exist for obtaining nanodroplets with a well defined size, we hope that these results will encourage experimentalists to investigate these interesting systems.
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Affiliation(s)
- Arnau Vilà
- Departament de Ciència dels Materials i Química Física and IQTC, Universitat de Barcelona, Martí i Franquès, 1-11, 08028 Barcelona, Spain.
| | - Miguel González
- Departament de Ciència dels Materials i Química Física and IQTC, Universitat de Barcelona, Martí i Franquès, 1-11, 08028 Barcelona, Spain.
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5
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Lahiri GK, Panda S, Huang KW, Singh A, Dey S. Inner-sphere electron transfer at the ruthenium-azo interface. Dalton Trans 2022; 51:2547-2559. [DOI: 10.1039/d1dt03934b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Metal complexes exhibiting multiple reversible redox states have drawn continuing research interest due to their electron reservoir features. In this context, the present article described ruthenium-acac complexes (acac=acetylacetonate) incorporating redox-active...
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6
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Cappelletti D, Cinti A, Nicoziani A, Falcinelli S, Pirani F. Molecular Beam Scattering Experiments as a Sensitive Probe of the Interaction in Bromine-Noble Gas Complexes. Front Chem 2019; 7:320. [PMID: 31157202 PMCID: PMC6534045 DOI: 10.3389/fchem.2019.00320] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 04/23/2019] [Indexed: 01/31/2023] Open
Abstract
This paper reports for the first time molecular beam experiments for the scattering of He, Ne, and Ar by the Br2 molecule, with the aim of probing in detail the intermolecular interaction. Measurements have been performed under the experimental condition to resolve the glory pattern, a quantum interference effect observable in the collision velocity dependence of the integral cross section. We analyzed the experimental data with a reliable potential model defined as a combination of an anisotropic van der Waals component with the additional contribution due to charge transfer and polar flattening effects related to the formation of an intermolecular halogen bond. The model involves few parameters, whose values are related to fundamental physical properties of the interacting partners, and it allows an internally consistent comparison of the stability of the gas-phase adducts formed by Br2 moiety with different noble gases as well as homologous complexes with the Cl2 molecule. The same model appears to be also easily generalized to describe the interaction of diatomic halogen molecules in the excited B(3Π) electronic state where the halogen bond contribution tends to vanish and more anisotropic van der Waals components dominate the structure of the complexes with noble gases.
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Affiliation(s)
- David Cappelletti
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
| | - Antonio Cinti
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
| | - Andrea Nicoziani
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
| | - Stefano Falcinelli
- Dipartimento di Ingegneria Civile ed Ambientale, Università degli Studi di Perugia, Perugia, Italy
| | - Fernando Pirani
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, Perugia, Italy
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7
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Pirani F, Cappelletti D, Falcinelli S, Cesario D, Nunzi F, Belpassi L, Tarantelli F. Selective Emergence of the Halogen Bond in Ground and Excited States of Noble‐Gas–Chlorine Systems. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201812889] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Fernando Pirani
- Dipartimento di Chimica, Biologia e BiotecnologieUniversità degli Studi di Perugia via Elce di Sotto 8 06213 Perugia Italy
| | - David Cappelletti
- Dipartimento di Chimica, Biologia e BiotecnologieUniversità degli Studi di Perugia via Elce di Sotto 8 06213 Perugia Italy
| | - Stefano Falcinelli
- Dipartimento di Ingegneria Civile ed AmbientaleUniversità degli Studi di Perugia via G. Duranti 93 06215 Perugia Italy
| | - Diego Cesario
- Dipartimento di Chimica, Biologia e BiotecnologieUniversità degli Studi di Perugia via Elce di Sotto 8 06213 Perugia Italy
- Department of Chemistry and Pharmaceutical Sciences and Amsterdam Center for Multiscale ModelingVrije Universiteit Amsterdam De Boelelaan 1083 1081 HV Amsterdam The Netherlands
| | - Francesca Nunzi
- Dipartimento di Chimica, Biologia e BiotecnologieUniversità degli Studi di Perugia via Elce di Sotto 8 06213 Perugia Italy
- Istituto di Scienze e Tecnologie Molecolari del CNR (ISTM-CNR) via Elce di Sotto 8 06123 Perugia Italy
| | - Leonardo Belpassi
- Istituto di Scienze e Tecnologie Molecolari del CNR (ISTM-CNR) via Elce di Sotto 8 06123 Perugia Italy
| | - Francesco Tarantelli
- Dipartimento di Chimica, Biologia e BiotecnologieUniversità degli Studi di Perugia via Elce di Sotto 8 06213 Perugia Italy
- Istituto di Scienze e Tecnologie Molecolari del CNR (ISTM-CNR) via Elce di Sotto 8 06123 Perugia Italy
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8
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Pirani F, Cappelletti D, Falcinelli S, Cesario D, Nunzi F, Belpassi L, Tarantelli F. Selective Emergence of the Halogen Bond in Ground and Excited States of Noble-Gas-Chlorine Systems. Angew Chem Int Ed Engl 2019; 58:4195-4199. [PMID: 30701641 DOI: 10.1002/anie.201812889] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 01/10/2019] [Indexed: 11/07/2022]
Abstract
Molecular-beam scattering experiments and theoretical calculations prove the nature, strength, and selectivity of the halogen bonds (XB) in the interaction of halogen molecules with the series of noble gas (Ng) atoms. The XB, accompanied by charge transfer from the Ng to the halogen, is shown to take place in, and measurably stabilize, the collinear conformation of the adducts, which thus becomes (in contrast to what happens for other Ng-molecule systems) approximately as bound as the T-shaped form. It is also shown how and why XB is inhibited when the halogen molecule is in the 3 Πu excited state. A general potential formulation fitting the experimental observables, based on few physically essential parameters, is proposed to describe the interaction accurately and is validated by ab initio computations.
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Affiliation(s)
- Fernando Pirani
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, via Elce di Sotto 8, 06213, Perugia, Italy
| | - David Cappelletti
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, via Elce di Sotto 8, 06213, Perugia, Italy
| | - Stefano Falcinelli
- Dipartimento di Ingegneria Civile ed Ambientale, Università degli Studi di Perugia, via G. Duranti 93, 06215, Perugia, Italy
| | - Diego Cesario
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, via Elce di Sotto 8, 06213, Perugia, Italy.,Department of Chemistry and Pharmaceutical Sciences and Amsterdam Center for Multiscale Modeling, Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081, HV, Amsterdam, The Netherlands
| | - Francesca Nunzi
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, via Elce di Sotto 8, 06213, Perugia, Italy.,Istituto di Scienze e Tecnologie Molecolari del CNR (ISTM-CNR), via Elce di Sotto 8, 06123, Perugia, Italy
| | - Leonardo Belpassi
- Istituto di Scienze e Tecnologie Molecolari del CNR (ISTM-CNR), via Elce di Sotto 8, 06123, Perugia, Italy
| | - Francesco Tarantelli
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, via Elce di Sotto 8, 06213, Perugia, Italy.,Istituto di Scienze e Tecnologie Molecolari del CNR (ISTM-CNR), via Elce di Sotto 8, 06123, Perugia, Italy
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9
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Li S, Zheng R, Chen SJ, Chen Y, Chen P. Investigations of the Rg-BrCl (Rg=He, Ne, Ar, Kr, Xe) binary van der Waals complexes: ab initio intermolecular potential energy surfaces, vibrational states and predicted pure rotational transition frequencies. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2017; 174:105-117. [PMID: 27888780 DOI: 10.1016/j.saa.2016.11.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Revised: 11/09/2016] [Accepted: 11/13/2016] [Indexed: 06/06/2023]
Abstract
The intermolecular potential energy surfaces (PESs) of the ground electronic state for the Rg-BrCl (Rg=He, Ne, Ar, Kr, Xe) van der Waals complexes have been constructed by using the coupled-cluster method in combination with the augmented quadruple-zeta correlation-consistent basis sets supplemented with an additional set of bond functions. The features of the anisotropic PESs for these complexes are remarkably similar, which are characterized by three minima and two saddle points between them. The global minimum corresponds to a collinear Rg-Br-Cl configuration. Two local minima, correlate with an anti-linear Rg-Cl-Br geometry and a nearly T-shaped structure, can also be located on each PES. The quantum bound state calculations enable us to investigate intermolecular vibrational states and rotational energy levels of the complexes. The transition frequencies are predicted and are fitted to obtain their corresponding spectroscopic constants. In general, the periodic trends are observed for this complex family. Comparisons with available experimental data for the collinear isomer of Ar-BrCl demonstrate reliability of our theoretical predictions, and our results for the other two isomers of Ar-BrCl as well as for other members of the complex family are also anticipated to be trustable. Except for the collinear isomer of Ar-BrCl, the data presented in this paper would be beneficial to improve our knowledge for these experimentally unknown species.
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Affiliation(s)
- Song Li
- School of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou, People's Republic of China.
| | - Rui Zheng
- School of Mathematics and Information Science, North China University of Water Resources and Electric Power, Zhengzhou, People's Republic of China
| | - Shan-Jun Chen
- School of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou, People's Republic of China
| | - Yan Chen
- School of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou, People's Republic of China
| | - Peng Chen
- School of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou, People's Republic of China
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10
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Valdés Á, Prosmiti R. Preferential stabilization of HeI2 van der Waals isomers: the effect of energetics and temperature. RSC Adv 2017. [DOI: 10.1039/c7ra01378g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Energetics and temperature dependence on the preferential stabilization of the linear/T-shaped HeI2 isomers.
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Affiliation(s)
- Álvaro Valdés
- Departamento de Física
- Universidad Nacional de Colombia
- Bogotá
- Colombia
| | - Rita Prosmiti
- Instituto de Física Fundamental (IFF-CSIC)
- CSIC
- 28006 Madrid
- Spain
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11
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Carrillo-Bohórquez O, Valdés Á, Prosmiti R. Temperature Dependence of HeBr 2 Isomers' Stability through Rovibrational Multiconfiguration Time-Dependent Hartree Calculations. J Phys Chem A 2016; 120:9458-9464. [PMID: 27802030 DOI: 10.1021/acs.jpca.6b09107] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The multiconfiguration time-dependent Hartree (MCTDH) method using a six-dimensional Hamiltonian that includes all rotational and vibrational degrees of freedom and an ab initio potential energy surface was employed to calculate the rovibronic states of the HeBr2 van der Waals complex. All rotational states of energies within 7 cm -1 with respect to the energy of the linear ground state were calculated without restriction of the total angular momentum. In total, we obtained 500 and 320 rotationally excited states of the ground vibrational T-shaped and linear isomers of the HeBr2, respectively, and compared them with those predicted by the rigid rotor model. A thermodynamic model was then introduced to determine the relative stability of the two conformers as a function of the temperature. On the basis of the present results, the linear conformers were found to be energetically more stable than the T-shaped ones by 1.14 cm-1 at T = 0 K, whereas conversion from linear to T-shaped complexes was observed at temperatures above 2.87 K.
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Affiliation(s)
- Orlando Carrillo-Bohórquez
- Departamento de Física, Universidad Nacional de Colombia , Calle 26, Cra 39, Edificio 404, Bogotá, Colombia
| | - Álvaro Valdés
- Departamento de Física, Universidad Nacional de Colombia , Calle 26, Cra 39, Edificio 404, Bogotá, Colombia
| | - Rita Prosmiti
- Institute of Fundamental Physics (IFF-CSIC), CSIC , Serrano 123, 28006 Madrid, Spain
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12
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Li L, Hu J, Shi X, Ruan W, Luo J, Wei X. Theoretical Studies on Structures, Properties and Dominant Debromination Pathways for Selected Polybrominated Diphenyl Ethers. Int J Mol Sci 2016; 17:ijms17060927. [PMID: 27322242 PMCID: PMC4926460 DOI: 10.3390/ijms17060927] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 06/01/2016] [Accepted: 06/03/2016] [Indexed: 12/03/2022] Open
Abstract
The B3LYP/6-311+G(d)-SDD method, which considers the relativistic effect of bromine, was adopted for the calculations of the selected polybrominated diphenyl ethers (PBDEs) in the present study, in which the B3LYP/6-311+G(d) method was also applied. The calculated values and experimental data for structural parameters of the selected PBDEs were compared to find the suitable theoretical methods for their structural optimization. The results show that the B3LYP/6-311+G(d) method can give the better results (with the root mean square errors (RMSEs) of 0.0268 for the C–Br bond and 0.0161 for the C–O bond) than the B3LYP/6-311+G(d)-SDD method. Then, the B3LYP/6-311+G(d) method was applied to predict the structures for the other selected PBDEs (both neutral and anionic species). The lowest unoccupied molecular orbital (LUMO) and the electron affinity are of a close relationship. The electron affinities (vertical electron affinity and adiabatic electron affinity) were discussed to study their electron capture abilities. To better estimate the conversion of configuration for PBDEs, the configuration transition states for BDE-5, BDE-22 and BDE-47 were calculated at the B3LYP/ 6-311+G(d) level in both gas phase and solution. The possible debromination pathway for BDE-22 were also studied, which have bromine substituents on two phenyl rings and the bromine on meta-position prefers to depart from the phenyl ring. The reaction profile of the electron-induced reductive debromination for BDE-22 were also shown in order to study its degradation mechanism.
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Affiliation(s)
- Lingyun Li
- Guizhou Provincial Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, Guiyang 550001, China.
| | - Jiwei Hu
- Guizhou Provincial Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, Guiyang 550001, China.
| | - Xuedan Shi
- Guizhou Provincial Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, Guiyang 550001, China.
| | - Wenqian Ruan
- Guizhou Provincial Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, Guiyang 550001, China.
| | - Jin Luo
- Guizhou Provincial Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment, Guizhou Normal University, Guiyang 550001, China.
| | - Xionghui Wei
- Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
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13
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Kalemos A, Valdés Á, Prosmiti R. Theoretical investigation of the He-I2(E3Πg) ion-pair state: ab initio intermolecular potential and vibrational levels. J Chem Phys 2012; 137:034303. [PMID: 22830698 DOI: 10.1063/1.4733983] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a theoretical study on the potential energy surface and vibrational bound states of the E electronic excited state of the HeI(2) van der Waals system. The interaction energies are computed using accurate ab initio methods and large basis sets. Relativistic small-core effective core potentials in conjunction with a quintuple-zeta quality basis set are employed for the heavy iodine atoms in multireference configuration interaction calculations for the (3)A' and (3)A" states. For the representation of the potential energy surface we used a general interpolation technique for constructing potential surfaces from ab initio data based on the reproducing kernel Hilbert space method. The surface presents global and local minima for T-shaped configurations with well-depths of 33.2 and 4.6 cm(-1), respectively. Vibrational energies and states are computed through variational quantum mechanical calculations. We found that the binding energy of the HeI(2)(E) T-shaped isomer is 16.85 cm(-1), in excellent agreement with recent experimental measurements. In lieu of more experimental data we also report our predictions on higher vibrational levels and we analyze the influence of the underlying surface on them. This is the first attempt to represent the potential surface of such a highly excited electronic state of a van der Waals complex, and it demonstrates the capability of the ab initio technology to provide accurate results for carrying out reliable studies to model experimental data.
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Affiliation(s)
- Apostolos Kalemos
- National and Kapodistrian University of Athens, Department of Chemistry, Laboratory of Physical Chemistry, Panepistimiopolis, Athens 15771, Greece.
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14
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Valdés Á, Prosmiti R, Villarreal P, Delgado-Barrio G. Theoretical investigation of the He4Br2 conformers. J Phys Chem A 2012; 116:7169-76. [PMID: 22667396 DOI: 10.1021/jp3026682] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Full dimensional quantum dynamics calculations of the three lowest isomers of the He(4)Br(2) van der Waals molecule in its ground electronic state are reported. The calculations are performed using the multiconfiguration time-dependent Hartree (MCTDH) method and a realistic potential form that includes the sum of three body ab initio coupled-cluster single double triple [CCSD(T)] He-Br(2) interactions plus the He-He and Br-Br interactions. This potential exhibits several multiple minima, with the three lowest ones lying very close in energy, just within 2 cm(-1). Such small differences are also found in the calculated binding energies of the three most stable conformers, indicating the floppiness of the system and, thus, the need of accurate potential forms and quantum full dynamics methods to treat this kind of complexes. The 12 dimensional results reported in this work present benchmark data and, thus, can serve to evaluate approximate methods aiming to describe higher order rare gas-dihalogen (N > 4) complexes. A comparison with previous studies using different potential forms and approaches to the energetics for the He(4)Br(2) cluster is also presented.
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Affiliation(s)
- Álvaro Valdés
- Instituto de Física Fundamental (IFF-CSIC), CSIC, Serrano 123, 28006 Madrid, Spain.
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Structure and dynamics of noble gas-halogen and noble gas ionic clusters: When theory meets experiment. Chem Phys 2012. [DOI: 10.1016/j.chemphys.2011.05.026] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Valdés A, Prosmiti R, Villarreal P, Delgado-Barrio G. Full-dimensional multi configuration time dependent Hartree calculations of the ground and vibrationally excited states of He2,3Br2 clusters. J Chem Phys 2011; 135:054303. [PMID: 21823696 DOI: 10.1063/1.3618727] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Quantum dynamics calculations are reported for the tetra-, and penta-atomic van der Waals He(N)Br(2) complexes using the multiconfiguration time-dependent Hartree (MCTDH) method. The computations are carried out in satellite coordinates, and the kinetic energy operator in this set of coordinates is given. A scheme for the representation of the potential energy surface based on the sum of the three-body HeBr(2) interactions at CSSD(T) level plus the He-He interaction is employed. The potential surfaces show multiple close lying minima, and a quantum description of such highly floppy multiminima systems is presented. Benchmark, full-dimensional converged results on ground vibrational/zero-point energies are reported and compared with recent experimental data available for all these complexes, as well as with previous variational quantum calculations for the smaller HeBr(2) and He(2)Br(2) complexes on the same surface. Some low-lying vibrationally excited eigenstates are also computed by block improved relaxation calculations. The binding energies and the corresponding vibrationally averaged structures are determined for different conformers of these complexes. Their relative stability is discussed, and contributes to evaluate the importance of the multiple-minima topology of the underlying potential surface.
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Affiliation(s)
- Alvaro Valdés
- Instituto de Física Fundamental (IFF-CSIC), CSIC, Madrid, Spain.
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Delgado-Tellez L, Valdés Á, Prosmiti R, Villarreal P, Delgado-Barrio G. Ab initio characterization of the Ne–I2 van der Waals complex: Intermolecular potentials and vibrational bound states. J Chem Phys 2011; 134:214304. [DOI: 10.1063/1.3596604] [Citation(s) in RCA: 21] [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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García-Gutierrez L, Delgado-Tellez L, Valdés Á, Prosmiti R, Villarreal P, Delgado-Barrio G. Intermolecular Ab Initio Potential and Spectroscopy of the Ground State of HeI2 Complex Revisited. J Phys Chem A 2009; 113:5754-62. [DOI: 10.1021/jp901250u] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Álvaro Valdés
- Instituto de Física Fundamental, C.S.I.C., Serrano 123, 28006 Madrid, Spain
| | - Rita Prosmiti
- Instituto de Física Fundamental, C.S.I.C., Serrano 123, 28006 Madrid, Spain
| | - Pablo Villarreal
- Instituto de Física Fundamental, C.S.I.C., Serrano 123, 28006 Madrid, Spain
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Boucher DS, Darr JP, Strasfeld DB, Loomis RA. Spectroscopic identification of higher-order rare gas-dihalogen complexes with different geometries: He(2,3)...Br(2) and He(2,3)...ICl. J Phys Chem A 2008; 112:13393-401. [PMID: 19053811 DOI: 10.1021/jp808368j] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Rovibronic transitions of multiple conformers of the He(2)...(79)Br(2)(X, v'' = 0), He(3)...(79)Br(2)(X, v'' = 0), He(2)...I(35)Cl(X, v'' = 0), and He(3)...I(35)Cl(X, v'' = 0) complexes stabilized in a pulsed, supersonic expansion are observed in action spectra recorded in the B-X region of the dihalogens. In addition to features associated with He(2)...(79)Br(2) and He(2)...I(35)Cl complexes with the rare gas atoms localized in the toroidal potential well lying in a plane perpendicular to the dihalogen bond, those associated with a ground-state conformer that has one He atom localized in the toroidal potential and the other He atom localized in the linear well at the end of the dihalogen moiety are also identified. Transitions of at least three conformers of the He(3)...Br(2) complex and two conformers of the He(3)...ICl complex are also observed. The relative populations of the different conformers are found to depend on where along the supersonic expansion the spectra are recorded, and thus on the local temperature regime sampled. The He(2)...(79)Br(2) and He(2)...I(35)Cl conformers with one He atom in each well are found to be the more stable conformers.
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Affiliation(s)
- David S Boucher
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, CB 1134, Saint Louis, Missouri 63130, USA
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González-Martínez M, Arbelo-González W, Rubayo-Soneira J, Bonnet L, Rayez JC. Vibrational predissociation of van der Waals complexes: Quasi-classical results with Gaussian-weighted trajectories. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2008.08.052] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Roncero O, de Lara-Castells MP, Delgado-Barrio G, Villarreal P, Stoecklin T, Voronin A, Rayez JC. Exact, Born-Oppenheimer, and quantum-chemistry-like calculations in helium clusters doped with light molecules: The He2N2(X) system. J Chem Phys 2008; 128:164313. [PMID: 18447445 DOI: 10.1063/1.2900560] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Helium clusters doped with diatomic molecules, He(N)-BC, have been recently studied by means of a quantum-chemistry-like approach. The model treats He atoms as "electrons" and dopants as "nuclei" in standard electronic structure calculations. Due to the large mass difference between He atoms and electrons, and to the replacement of Coulomb interactions by intermolecular potentials, it is worth assessing up to what extent are the approximations involved in this model, i.e., decoupling of the BC rotation from the He-atom orbital angular momenta and Born-Oppenheimer separation of the BC stretch versus the He motions, accurate enough. These issues have been previously tackled elsewhere for the (4)He(2)-Br(2)(X) system, which contains a heavy dopant [Roncero et al., Int. J. Quantum Chem. 107, 2756 (2007)]. Here, we consider a similar cluster but with a much lighter dopant such as N(2)(X). Although the model does not provide the correct energy levels for the cluster, positions and intensities of the main detectable lines of the vibrotational Raman spectrum at low temperature are accurately reproduced.
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Affiliation(s)
- O Roncero
- Instituto de Física Fundamental (C.S.I.C.), Serrano 123, E-28006 Madrid, Spain
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Diez-Pardos C, Valdés A, Prosmiti R, Villarreal P, Delgado-Barrio G. Additive intermolecular potentials from ab initio calculations: trends in Rg2–dihalogen van der Waals trimers. Theor Chem Acc 2007. [DOI: 10.1007/s00214-007-0368-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Valdés A, Prosmiti R, Villarreal P, Delgado-Barrio G, Lemoine D, Lepetit B. Ab initiovibrational predissociation dynamics of He–I2(B) complex. J Chem Phys 2007; 126:244314. [PMID: 17614556 DOI: 10.1063/1.2748404] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Three-dimensional quantum mechanical calculations on the vibrational predissociation dynamics of HeI2 B state complex are performed using a potential energy surface accurately fitted to unrestricted open-shell coupled cluster ab initio data, further enabling extrapolation for large I2 bond lengths. A Lanczos iterative method with an optimized complex absorbing potential is used to determine energies and lifetimes of the vibrationally predissociating He,I2(B,v') complex for v'<or=26 of I2 vibrational excitations. The calculated predissociating state energies agree with recent experimental results within 0.5 cm(-1). This excellent agreement is remarkable since no adjustment was made with respect to the experiments. The present ab initio approach, however, shows its limitations in the fact that the computed lifetimes that are highly sensitive to subtle details of the potential energy surfaces such as anisotropy, are a factor of 1.5 larger than the available experimental data.
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Affiliation(s)
- Alvaro Valdés
- Instituto de Matemáticas y Física Fundamental, CSIC, Serrano 123, 28006 Madrid, Spain
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Ray SE, McCoy AB, Glennon JJ, Darr JP, Fesser EJ, Lancaster JR, Loomis RA. Experimental and theoretical investigations of the He⋯I2 rovibronic spectra in the I2 B–X, 20–0 region. J Chem Phys 2006; 125:164314. [PMID: 17092080 DOI: 10.1063/1.2363378] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The laser-induced fluorescence and action spectra of I2 in a helium supersonic expansion have been recorded in the I2 B-X, 20-0 region. Two features are identified within the spectra. The lower-energy feature arises from transitions between states that are localized in a T-shaped conformation on both the X- and B-state potentials. The higher-energy feature reflects transitions from states that are localized in a linear conformation on the X state to states that have energies that are larger than the barrier for free rotation of the rare gas atom about the I2 molecule on the B-state potential. Ground-state binding energies of 16.6(6) and 16.3(6) cm-1 were determined for the T-shaped and linear conformers, respectively. These spectra are compared to those calculated using the experimentally determined rotational temperatures. Based on the agreement between the experimental and calculated spectra, the binding energies of the J'=0 states with 0 and 2-6 quanta of excitation in the He...I2 bending mode on the B state were determined. Several models for the B-state potential were used to investigate the origins of the shape of the contour of the higher-energy feature in the spectra for He...I2 and He...Br2. The shape of the contours was found to be relatively insensitive to the choice of potential. This leads us to believe that the spectra of these systems are relatively insensitive to the parameters of the B-state potential energy surface and are more sensitive to properties of the halogen molecule.
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Affiliation(s)
- Sara E Ray
- Department of Chemistry, The Ohio State University, Columbus, Ohio 43210, USA
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Valdés A, Prosmiti R, Villarreal P, Delgado-Barrio G. A theoretical study of He2ICl van der Waals cluster. J Chem Phys 2006; 125:014313. [PMID: 16863304 DOI: 10.1063/1.2208614] [Citation(s) in RCA: 32] [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 structure, energetics, and dynamics of He2ICl complex in its ground state are studied by means of ab initio electronic structure and quantum-mechanical calculations. Interaction energies for selected He2ICl configurations are calculated at the coupled-cluster [CCSD(T)] level of theory using a large-core pseudopotential for the I atom and the aug-cc-pVTZ and aug-cc-pV5Z basis sets for the Cl and He atoms, respectively. The surface is characterized around its lower five minima and the minimum energy pathways through them. The global minimum of the potential corresponds to a "police-nightstick (1)" configuration, the second one to a linear, the next one to tetrahedral configuration, and the following two to "bifork" and "police-nightstick (2)" structures, with well depths of -99.12, -97.42, -88.32, -85.84, and -78.54 cm(-1), respectively. An analytical form based on the sum of the three-body parametrized HeICl interactions plus the He-He interaction is found to represent very well the tetra-atomic CSSD(T) results. The present potential expression is employed to perform variational five-dimensional quantum-mechanical calculations to study the vibrational bound states of the van der Waals He2ICl complex. Results for total angular momentum J = 0 provide the binding energy D0 and the corresponding vibrationally averaged structure for different isomers of the cluster. Comparison of these results with recent experimental observations further justifies the potential used in this work.
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Affiliation(s)
- Alvaro Valdés
- Instituto de Matemáticas y Física Fundamental, CSIC, Serrano 123, 28006 Madrid, Spain
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García-Vela A. An empirical potential-energy surface for the He–I2(BΠu3) van der Waals complex including three-body effects. J Chem Phys 2005; 123:124311. [PMID: 16392486 DOI: 10.1063/1.2040367] [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
An empirical intermolecular potential surface is proposed for the He-I2(B 3IIu) complex, modeled as a sum of pairwise He-I Morse interactions plus a three-body interaction term. The potential reproduces with very good agreement the spectral blueshifts and vibrational predissociation lifetimes measured for He-I2(B,v') in the range v' = 10-67 of I2 vibrational excitations. In particular, the accuracy achieved in the description of the experimental data for high v' levels is attributed to the three-body interaction term included in the potential. The behavior of the potential surface with the I-I separation is analyzed and correlated with the experimental findings.
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Affiliation(s)
- A García-Vela
- Instituto de Matemáticas y Física Fundamental, Consejo Superior de Investigaciones Cientificas (CSIC), Serrano 123, 28006 Madrid, Spain.
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Boucher DS, Strasfeld DB, Loomis RA, Herbert JM, Ray SE, McCoy AB. Stabilization and rovibronic spectra of the T-shaped and linear ground-state conformers of a weakly bound rare-gas–homonuclear dihalogen complex: He⋯Br2. J Chem Phys 2005; 123:104312. [PMID: 16178602 DOI: 10.1063/1.2006675] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Laser-induced fluorescence spectra of Br(2) entrained in a He supersonic expansion have been recorded in the Br(2) B-X, 8-0, 12-0, and 21-0 spectral regions at varying downstream distances, and thus different temperature regimes. Features associated with transitions of the T-shaped and linear He...Br(2)(X,nu(") = 0) complexes are identified. The changes in the relative intensities of the T-shaped and linear features with cooling in the expansion indicate that the linear conformer is energetically more stable than the T-shaped conformer. A He + Br(2)(X,nu(") = 0) ab initio potential-energy surface, computed at the coupled cluster level of theory with a large, flexible basis set, is used to calculate the binding energies of the two conformers, 15.8 and 16.5 cm(-1) for the T-shaped and linear complexes, respectively. This potential and an excited-state potential [M. P. de Lara-Castells, A. A. Buchachenko, G. Delgado-Barrio, and P. Villareal, J. Chem. Phys. 120, 2182 (2004)] are used to calculate the excitation spectra of He...(79)Br(2)(X,nu(") = 0) in the Br(2) B-X, 12-0 region. The calculated spectra are used to make spectral assignments and to determine the energies of the excited-state intermolecular vibrational levels accessed in the observed transitions. Temperature-dependent laser-induced fluorescence spectra and a simple thermodynamic model [D. S. Boucher, J. P. Darr, M. D. Bradke, R. A. Loomis, and A. B. McCoy, Phys. Chem. Chem. Phys. 6, 5275 (2004)] are used to estimate that the linear conformer is 0.4(2) cm(-1) more strongly bound than the T-shaped conformer. Two-laser action spectroscopy experiments reveal that the binding energy of the linear He...(79)Br(2)(X,nu(") = 0) conformer is 17.0(8) cm(-1), and that of the T-shaped He...(79)Br(2)(X,nu(") = 0) conformer is then 16.6(8) cm(-1), in good agreement with the calculated values.
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Affiliation(s)
- David S Boucher
- Department of Chemistry, Washington University in St. Louis, CB 1134, Missouri, 63130, USA
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García-Vela A. An empirical potential energy surface for the He-Br2 (B3pi(u)) van der Waals complex. J Phys Chem A 2005; 109:5545-52. [PMID: 16833885 DOI: 10.1021/jp051167n] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
An empirical potential energy surface is proposed for the He-Br2 (B3pi(u)) complex. The intermolecular potential is modeled as a sum of pairwise He-Br Morse interactions plus a three-body interaction term. The parameters of the potential are fitted in order to reproduce the spectral blue-shifts and vibrational predissociation line widths measured for He-79Br2 (B, v') in the range v' = 8-48 of Br2 vibrational excitations. The calculated blue-shifts and line widths are in very good agreement with the measurements (typically within experimental error or close to its limits) along the whole range of v' levels studied. It is particularly remarkable to note the accuracy provided by the interaction surface in the region of high v' excitations (v' > 35), where three-body effects become important. The behavior of the potential surface with the Br-Br separation is analyzed and correlated with the experimental findings.
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Affiliation(s)
- A García-Vela
- Instituto de Matematicas y Física Fundamental, C.S.I.C., Serrano 123, 28006 Madrid, Spain.
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Abstract
The intermolecular potential surface of He-CH(3)F is investigated through ab initio calculations and microwave and millimeter-wave spectroscopies. The intermolecular potential is calculated at the fourth-order Møller-Plesset level with a large basis set including bond functions. Three minimums exist, the deepest of which is at the carbon end of the C-F axis and has a depth of 46.903 cm(-1), the second deepest is in a T-shaped position relative to the C-F axis with a depth of 44.790 cm(-1), and the shallowest is at the fluorine end of the C-F axis with a depth of 30.929 cm(-1). The barrier to internal rotation of the CH(3)F subunit about its C-F axis is very low, thus leading to essentially free internal rotation and two separate sets of bound states correlating to ortho-CH(3)F (|K| = 3n) for the ground, or A, internal rotor state upon which this study focuses, and to para-CH(3)F (|K| = 3n +/- 1) for the excited, or E, internal rotor state. Bound-state calculations of the A state performed using two different techniques show the lowest-energy state to have the helium localized in the T-shaped well with an energy of -11.460 cm(-1), while two excited configurations of the A state have the helium localized either in the well at the carbon end ("linear") with an energy of -7.468 cm(-1) or in the well at the fluorine end ("antilinear") with an energy of -4.805 cm(-1). Spectroscopic observations confirm the predicted energy-level structure of the ground and first excited states. Sixteen transitions between 12 distinct energy levels have been observed, including pure rotational transitions of both the T-shaped ground state and the linear excited state, as well as rovibrational transitions between the ground state and the linear excited state. The energy difference between the T-shaped state and the linear state is measured to be 132 374.081(16) MHz. There is significant Coriolis mixing of the ground state J(K(a)K(c)) = 2(20) and the linear J(K) = 2(0) levels which aided in the observation of the T to linear transitions. This mixing and the T to linear energy difference are sensitive probes of the relative well depths of the two lowest minimums and are well predicted by the ab initio potential. Improved agreement between experiment and theory is obtained by morphing the correlation energy of the potential. He-CH(3)F is one of just a few atom-molecule complexes for which the ground-state geometry does not coincide with the global potential minimum.
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Affiliation(s)
- Kelly J Higgins
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
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