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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: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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Puentes-Milián L, García-Alfonso E, Márquez-Mijares M, Rubayo-Soneira J. NeI 2 Photofragmentation Dynamics Through Quasiclassical and Semiclassical Studies. Chemphyschem 2023; 24:e202300406. [PMID: 37503677 DOI: 10.1002/cphc.202300406] [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: 06/09/2023] [Revised: 07/26/2023] [Accepted: 07/26/2023] [Indexed: 07/29/2023]
Abstract
The triatomic system NeI2 is studied under the consideration that the diatom is found in an excited electronic state (B). The vibrational levels (v=13, …, 23) are considered within two well-known theoretical procedures: quasi-classical trajectories (QCT), where the classical equations of motion for nuclei are solved on a single potential energy surface (PES), and the trajectory surface hopping (TSH) method, where the same are solved in a bunch of crossed vibrational PES (diabatic representation). The trajectory surface hopping fewest switches (TSHFS) is implemented to minimize the number of hoppings, thus allowing the calculations of hopping probability between the different PES's, and the kinetic mechanism to track the dissociation path. From these calculations, several observables such as, the lifetimes, vibrational and rotational energies (I2 ), dissociation channels, are obtained. Our results are compared with previous experimental and theoretical work.
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Affiliation(s)
- Loidel Puentes-Milián
- Instituto Superior de Tecnologías y Ciencias Aplicadas (InSTEC), Universidad de La Habana (UH), Ave. Salvador Allende 1110, Plaza de la Revolución, 10400, La Habana, Cuba
| | - Ernesto García-Alfonso
- Université Toulouse 3 and CNRS, Laboratoire des Collisions, Agrégats et Réactivité, IRSAMC, 118 Route de Narbonne, 31062, Toulouse, Cedex 09, France
| | - Maykel Márquez-Mijares
- Instituto Superior de Tecnologías y Ciencias Aplicadas (InSTEC), Universidad de La Habana (UH), Ave. Salvador Allende 1110, Plaza de la Revolución, 10400, La Habana, Cuba
| | - Jesús Rubayo-Soneira
- Instituto Superior de Tecnologías y Ciencias Aplicadas (InSTEC), Universidad de La Habana (UH), Ave. Salvador Allende 1110, Plaza de la Revolución, 10400, La Habana, Cuba
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3
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Ghanmi C, Nakbi H, Al-Qarni HJ, Alharzali N, Berriche H. Structure, energetics, and spectroscopy of the K 2+(X 2Σ +g) interacting with the noble gas atoms Ar, Kr and Xe. J Mol Graph Model 2023; 120:108413. [PMID: 36758327 DOI: 10.1016/j.jmgm.2023.108413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 12/31/2022] [Accepted: 01/12/2023] [Indexed: 02/05/2023]
Abstract
The structure, energetic, and spectroscopy properties of the ionic system K2+(X2Σ+g) interacting with the noble gas atoms Argon, Krypton and Xenon are studied. The computations are done by an accurate ab initio approach based on the pseudo-potential technique, Gaussian basis sets, parameterized l-dependent polarization potentials and an analytic potential form for the K+Ar, K+Kr and K+Xe interactions. These interactions are added via the CCSD(T) potential taken from literature and fitted applying the analytical expression of Tang and Toennies. The application of the pseudo-potential approach reduces the number of active electrons of each complex to only one electron. The potential energy surfaces are analyzed on a large range of the Jacobi coordinates, R and θ. By the general interpolation outline based on the RKHS (Reproducing Kernel Hilbert Space) procedure, we have reproduced for each complex from our ab initio results the two-dimensional contour plots of an analytical potential. To evaluate the stability of each complex, we have determined from the potential energy surfaces the equilibrium distance (Re), the well depth (De), the quantum energy (D0), the zero-point-energy (ZPE) and the ZPE%. The results showed that the linear configurations, where the noble gas atom connected to the K2+(X2Σ+g) system, are the more stable.
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Affiliation(s)
- Chedli Ghanmi
- Laboratory of Interfaces and Advanced Materials, Faculty of Science, University of Monastir, 5019, Monastir, Tunisia.
| | - Haifa Nakbi
- Laboratory of Interfaces and Advanced Materials, Faculty of Science, University of Monastir, 5019, Monastir, Tunisia
| | - Hind Jahman Al-Qarni
- Physics Department, College of Science and Arts, Balqarn, Bisha University, Saudi Arabia
| | - Nisrin Alharzali
- Laboratory of Interfaces and Advanced Materials, Faculty of Science, University of Monastir, 5019, Monastir, Tunisia
| | - Hamid Berriche
- Laboratory of Interfaces and Advanced Materials, Faculty of Science, University of Monastir, 5019, Monastir, Tunisia; Mathematics and Natural Sciences Department, School of Arts and Sciences, American University of Ras Al Khaimah, Ras Al Khaimah, United Arab Emirates.
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4
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Alharzali N, Rodríguez-Segundo R, Prosmiti R. Modelling interactions of cationic dimers in He droplets: microsolvation trends in He nK 2+ clusters. Phys Chem Chem Phys 2021; 23:7849-7859. [PMID: 33220666 DOI: 10.1039/d0cp05406b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the results of a detailed theoretical investigation of small K2+-doped He clusters. The structural characteristics and stabilities of such cations are determined from ab initio electronic structure calculations at the MRCI+Q level of theory. The underlying interactions show a multireference character and such effects are analyzed. The interaction potentials are constructed employing an interpolation technique within the inverse problem theory method, while the nuclear quantum effects are computed for the trimers, their spatial arrangements are discussed, and information was extracted on the orientational anisotropy of the forces. We found that energetically the most stable conformer corresponds to linear arrangements that are taking place under large amplitude vibrations, with high zero-point energy. We have further looked into the behavior of higher-order species with various He atoms surrounding the cationic dopant. By using a sum of potentials approach and an evolutionary programming method, we analyzed the structural stability of clusters with up to six He atoms in comparison with interactions energies obtained from MRCI+Q quantum chemistry computations. Structures containing Hen motifs that characterize pure rare gas clusters, appear for the larger K2+-doped He clusters, showing selective growth during the microsolvation process of the alkali-dimer cation surrounded by He atoms. Such results indicate the existence of local solvation microstructures in these aggregates, where the cationic impurity could get trapped for a short time, contributing to the slow ionic mobility observed experimentally in ultra-cold He-droplets.
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Affiliation(s)
- Nissrin Alharzali
- Institute of Fundamental Physics (IFF-CSIC), CSIC, Serrano 123, 28006 Madrid, Spain.
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Duragkar A, Dhoble N, Kadam AR, Dhoble S. Enhanced photoluminescence in RE (Eu
3+
, Ce
3+
and Sm
3+
)‐activated Ca
10
(PO
4
)F
2
phosphors by double or triple ionized mineral doping: a comparative study. LUMINESCENCE 2020; 36:606-620. [DOI: 10.1002/bio.3977] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 10/12/2020] [Accepted: 10/27/2020] [Indexed: 12/13/2022]
Affiliation(s)
- Arati Duragkar
- Department of Chemistry Sevadal Mahila Mahavidyalaya Nagpur India
| | - N.S. Dhoble
- Department of Chemistry Sevadal Mahila Mahavidyalaya Nagpur India
| | | | - S.J. Dhoble
- Department of Physics R.T.M. Nagpur University Nagpur India
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6
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Andreev AS, Baturo VV, Lukashov SS, Poretsky SA, Pravilov AM, Zhironkin AI. Experimental and theoretical investigations of HeNeI 2 trimer. J Chem Phys 2020; 152:234307. [DOI: 10.1063/5.0008760] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Aleksei S. Andreev
- Department of Physics, Saint Petersburg State University, SPbSU, 7/9 Universitetskaya nab., Saint Petersburg 199034, Russia
| | - Vera V. Baturo
- Department of Physics, Saint Petersburg State University, SPbSU, 7/9 Universitetskaya nab., Saint Petersburg 199034, Russia
| | - Sergey S. Lukashov
- Department of Physics, Saint Petersburg State University, SPbSU, 7/9 Universitetskaya nab., Saint Petersburg 199034, Russia
| | - Sergey A. Poretsky
- Department of Physics, Saint Petersburg State University, SPbSU, 7/9 Universitetskaya nab., Saint Petersburg 199034, Russia
| | - Anatoly M. Pravilov
- Department of Physics, Saint Petersburg State University, SPbSU, 7/9 Universitetskaya nab., Saint Petersburg 199034, Russia
| | - Anatoly I. Zhironkin
- Department of Physics, Saint Petersburg State University, SPbSU, 7/9 Universitetskaya nab., Saint Petersburg 199034, Russia
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Nunzi F, Di Erasmo B, Tarantelli F, Cappelletti D, Pirani F. The Halogen-Bond Nature in Noble Gas-Dihalogen Complexes from Scattering Experiments and Ab Initio Calculations. Molecules 2019; 24:molecules24234274. [PMID: 31771210 PMCID: PMC6930525 DOI: 10.3390/molecules24234274] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 11/21/2019] [Accepted: 11/21/2019] [Indexed: 11/16/2022] Open
Abstract
In order to clarify the nature of the halogen bond (XB), we considered the prototype noble gas–dihalogen molecule (Ng–X2) systems, focusing on the nature, range, and strength of the interaction. We exploited data gained from molecular beam scattering experiments with the measure of interference effects to obtain a suitable formulation of the interaction potential, with the support of high-level ab initio calculations, and charge displacement analysis. The essential interaction components involved in the Ng–X2 adducts were characterized, pointing at their critical balance in the definition of the XB. Particular emphasis is devoted to the energy stability of the orientational Ng–X2 isomers, the barrier for the X2 hindered rotation, and the influence of the X2 electronic state. The present integrated study returns reliable force fields for molecular dynamic simulations in Ng–X2 complexes that can be extended to systems with increasing complexity and whose properties depend on the selective formation of XB.
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Affiliation(s)
- Francesca Nunzi
- Dipartimento di Chimica, Biologia e Biotecnologie, via Elce di Sotto 8, I-06123 Perugia, Italy; (B.D.E.); (F.T.); (D.C.)
- Istituto CNR di Scienze e Tecnologie Chimiche “Giulio Natta” (CNR-SCITEC), via Elce di Sotto, I-06123 Perugia, Italy
- Correspondence: (F.N.); (F.P.)
| | - Benedetta Di Erasmo
- Dipartimento di Chimica, Biologia e Biotecnologie, via Elce di Sotto 8, I-06123 Perugia, Italy; (B.D.E.); (F.T.); (D.C.)
| | - Francesco Tarantelli
- Dipartimento di Chimica, Biologia e Biotecnologie, via Elce di Sotto 8, I-06123 Perugia, Italy; (B.D.E.); (F.T.); (D.C.)
- Istituto CNR di Scienze e Tecnologie Chimiche “Giulio Natta” (CNR-SCITEC), via Elce di Sotto, I-06123 Perugia, Italy
| | - David Cappelletti
- Dipartimento di Chimica, Biologia e Biotecnologie, via Elce di Sotto 8, I-06123 Perugia, Italy; (B.D.E.); (F.T.); (D.C.)
| | - Fernando Pirani
- Dipartimento di Chimica, Biologia e Biotecnologie, via Elce di Sotto 8, I-06123 Perugia, Italy; (B.D.E.); (F.T.); (D.C.)
- Correspondence: (F.N.); (F.P.)
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8
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Valdés Á, Prosmiti R. Quantum effects on the stability of the He 5 I 2 van der Waals conformers. J Comput Chem 2019; 40:2200-2206. [PMID: 31148224 DOI: 10.1002/jcc.25870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 04/10/2019] [Accepted: 05/16/2019] [Indexed: 11/05/2022]
Abstract
We present 15-dimensional quantum multiconfiguration time-dependent Hartree calculations of the vibrational levels of the He5 I2 van der Waals (vdW) complex employing an ab initio-based potential energy surface (PES). The energies and spatial features of such bound structures are analyzed, providing predictions on the structures and relative stabilities of its three lowest isomers. We found that the most stable isomer corresponds to all five He atoms encircling the I2 molecule, indicating that in this case the anharmonic quantum effects do not stabilize the isomers involving a He atom in a linear configuration as reported previously for the smaller HeN I2 systems. Such finding provides information on the overall structuring of the finite-size-solvent systems, highlighting the intriguing interplay between weak intermolecular interactions and quantum effects. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Álvaro Valdés
- Departamento de Física, Universidad Nacional de Colombia, Calle 26, Cra 39, Edificio 404, Bogotá, Colombia
| | - Rita Prosmiti
- Departamento PAMS, Instituto de Física Fundamental (IFF-CSIC), CSIC, Serrano 123, 28006, Madrid, Spain
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10
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Pérez de Tudela R, Barragán P, Valdés Á, Prosmiti R. Energetics and solvation structure of a dihalogen dopant (I2) in (4)He clusters. J Phys Chem A 2014; 118:6492-500. [PMID: 24869502 DOI: 10.1021/jp502994g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The energetics and structure of small HeNI2 clusters are analyzed as the size of the system changes, with N up to 38. The full interaction between the I2 molecule and the He atoms is based on analytical ab initio He-I2 potentials plus the He-He interaction, obtained from first-principle calculations. The most stable structures, as a function of the number of solvent He atoms, are obtained by employing an evolutionary algorithm and compared with CCSD(T) and MP2 ab initio computations. Further, the classical description is completed by explicitly including thermal corrections and quantum features, such as zero-point-energy values and spatial delocalization. From quantum PIMC calculations, the binding energies and radial/angular probability density distributions of the thermal equilibrium state for selected-size clusters are computed at a low temperature. The sequential formation of regular shell structures is analyzed and discussed for both classical and quantum treatments.
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11
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Valdés Á, Prosmiti R. Quantum mechanical characterization of the He4ICl weakly bound complex. J Phys Chem A 2013; 117:7217-23. [PMID: 23537513 DOI: 10.1021/jp4011263] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Vibrational calculations are performed for the 12-dimensional He4ICl van der Waals complex using the multiconfiguration time-dependent Hartree (MCTDH) method. The potential energy surface of the cluster is represented as a sum of the triatomic He-ICl ab initio parametrized terms plus the He-He interactions. The topology of the potential presents higher anisotropy compared to the one with a homonuclear dopant, and this is clearly reflected in the structure and energetics of the low-lying conformers of the system. In order to take advantage of the MCTDH method, natural potential fits are employed for the potential energy operator, and also, a mode combination scheme is introduced in order to speed up the computations. Zero-point energy, binding energies, and vibrationally averaged structures of different isomers of the He4ICl cluster are obtained. The present results predict that the (3,1,0) structure, involving three He atoms in the near T-shaped and one He atom in the linear configurations, to be the most stable one in accord with recent experimental findings. Comparisons with previous theoretical and experimental data are presented, and the stability of the high-order conformers is discussed in connection with the multiple minima (global and local) of the underlying potential surface.
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Affiliation(s)
- Álvaro Valdés
- Instituto de Física Fundamental (IFF-CSIC), CSIC, Serrano 123, 28006 Madrid, Spain
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12
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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: 16] [Impact Index Per Article: 1.3] [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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13
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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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15
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Kalemos A, Valdés A, Prosmiti R. An ab initio study of the E 3Πg state of the iodine molecule. J Phys Chem A 2012; 116:2366-70. [PMID: 22295971 DOI: 10.1021/jp3000202] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The E (3)Π(g) state of the iodine molecule is studied by ab initio multireference methods coupled with effective core potentials and large basis sets. Two potential minima are found, a global featuring an ion-pair character, and a local presenting a purely Rydberg nature. Four avoided crossings along the dissociation coordinate attribute an interesting topology to its potential energy curve, and their effect on the vibrational levels of I(2) is discussed.
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Affiliation(s)
- Apostolos Kalemos
- Laboratory of Physical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Athens, Hellas.
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16
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Valdés A, Prosmiti R, Villarreal P, Delgado-Barrio G. Theoretical characterization of intermolecular vibrational states through the multi-configuration time dependent Hartree approach: the He2,3ICl clusters. J Chem Phys 2011; 135:244309. [PMID: 22225158 DOI: 10.1063/1.3671611] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Benchmark, full-dimensional calculations on the ground and excited vibrational states for the tetra-, and penta-atomic weakly bound He(2,3)ICl complexes are reported. The representation of the potential energy surfaces includes three-body HeICl potentials parameterized to coupled-cluster singles, doubles, and perturbative triples ab initio data. These terms are important in accurately describing the interactions of such highly floppy systems. The corresponding 6D/9D computations are performed with the multi-configuration time dependent Hartree method, using natural potential fits, and a mode combination scheme to optimize the computational effort in the improved relaxation calculations. For these complexes several low-lying vibrational states are computed, and their binding energies and radial/angular probability density distributions are obtained. We found various isomers which are assigned to different structural models related with combinations of the triatomic isomers, like linear, T-shaped, and antilinear ones. Comparison of these results with recent experimental data is presented, and the quantitative deviations found with respect to the experiment are discussed.
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Affiliation(s)
- Alvaro Valdés
- Instituto de Física Fundamental (IFF-CSIC), CSIC, Madrid, Spain.
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17
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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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