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DuránCaballero L, Schran C, Brieuc F, Marx D. Neural network interaction potentials for para-hydrogen with flexible molecules. J Chem Phys 2022; 157:074302. [DOI: 10.1063/5.0100953] [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 study of molecular impurities in para-hydrogen ( pH2) clusters is key to push forward our understanding of intra- and intermolecular interactions, including their impact on the superfluid response of this bosonic quantum solvent. This includes tagging with only one or very few pH2, the microsolvation regime for intermediate particle numbers, and matrix isolation with many solvent molecules. However, the fundamental coupling between the bosonic pH2 environment and the (ro-)vibrational motion of molecular impurities remains poorly understood. Quantum simulations can, in principle, provide the necessary atomistic insight, but they require very accurate descriptions of the involved interactions. Here, we present a data-driven approach for the generation of impurity⋯ pH2 interaction potentials based on machine learning techniques, which retain the full flexibility of the dopant species. We employ the well-established adiabatic hindered rotor (AHR) averaging technique to include the impact of the nuclear spin statistics on the symmetry-allowed rotational quantum numbers of pH2. Embedding this averaging procedure within the high-dimensional neural network potential (NNP) framework enables the generation of highly accurate AHR-averaged NNPs at coupled cluster accuracy, namely, explicitly correlated coupled cluster single, double, and scaled perturbative triples, CCSD(T*)-F12a/aVTZcp, in an automated manner. We apply this methodology to the water and protonated water molecules as representative cases for quasi-rigid and highly flexible molecules, respectively, and obtain AHR-averaged NNPs that reliably describe the corresponding H2O⋯ pH2 and H3O+⋯ pH2 interactions. Using path integral simulations, we show for the hydronium cation, H3O+, that umbrella-like tunneling inversion has a strong impact on the first and second pH2 microsolvation shells. The automated and data-driven nature of our protocol opens the door to the study of bosonic pH2 quantum solvation for a wide range of embedded impurities.
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Affiliation(s)
- Laura DuránCaballero
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Christoph Schran
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Fabien Brieuc
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
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2
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Otani H, Nakahara H, Goto H, Kuma S, Momose T. Electronic spectroscopy of Mg-phthalocyanine embedded in cold hydrogen clusters produced by a pulsed nozzle. J Chem Phys 2021; 155:044309. [PMID: 34340371 DOI: 10.1063/5.0056499] [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
Cold clusters of molecular hydrogen were created using a pulsed nozzle. The thermodynamical states of the clusters were characterized by measuring the cluster beam velocity and the laser-induced fluorescence (LIF) spectra of embedded molecules. Two distinct velocity components were identified in the beam that originates from different clustering mechanisms. The fast velocity component corresponds to the expansion of H2 from the gas phase, while the slow velocity component corresponds to the expansion from the liquid phase. The velocity distribution of these two components showed no significant difference between the expansions of para and normal hydrogen. In this study, LIF spectroscopy of single Mg-phthalocyanine molecules embedded in the H2 clusters consisting of 105 H2 molecules was used to investigate the properties of the fast component. The observed peak frequencies of the LIF signals, compared to those observed in helium droplets, were used to infer the possible presence of the liquid phase in the fast component of the H2 clusters below 5 K. The shift, linewidth, and splitting in the spectra, which strongly depend on the ortho/para ratio, are attributed to the local configurations of hydrogen in the vicinity of the probe molecules.
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Affiliation(s)
- Hatsuki Otani
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Hiroko Nakahara
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Haruka Goto
- Division of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Susumu Kuma
- Atomic, Molecular, and Optical Physics Laboratory, RIKEN, Saitama 351-0198, Japan
| | - Takamasa Momose
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
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3
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Brieuc F, Schran C, Uhl F, Forbert H, Marx D. Converged quantum simulations of reactive solutes in superfluid helium: The Bochum perspective. J Chem Phys 2020; 152:210901. [DOI: 10.1063/5.0008309] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Affiliation(s)
- Fabien Brieuc
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Christoph Schran
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Felix Uhl
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Harald Forbert
- Center for Solvation Science ZEMOS, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
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Liu JM, Zhai Y, Li H. Explicit correlation treatment of the six-dimensional potential energy surface and predicted infrared spectra for OCS–H2. J Chem Phys 2017; 147:044313. [DOI: 10.1063/1.4996086] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Jing-Min Liu
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, 2519 Jiefang Road, Changchun 130023, People’s Republic of China
| | - Yu Zhai
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, 2519 Jiefang Road, Changchun 130023, People’s Republic of China
| | - Hui Li
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, 2519 Jiefang Road, Changchun 130023, People’s Republic of China
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Raston PL, Jäger W. Rotational Spectroscopic Study of Quantum Solvation in Isotopologic ( pH 2) N–CO Clusters. J Phys Chem A 2017; 121:3671-3678. [DOI: 10.1021/acs.jpca.7b02192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Paul L. Raston
- Department
of Chemistry and Biochemistry, James Madison University, Harrisonburg, Virginia 22807, United States
| | - Wolfgang Jäger
- Department
of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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6
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Hoshina H, Sliter R, Ravi A, Kuma S, Momose T, Vilesov AF. Ro‐vibrational Spectra of (
para
‐H
2
)
N
‐CH
4
in He Droplets. Chemphyschem 2016; 17:3818-3825. [DOI: 10.1002/cphc.201600484] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Hiromichi Hoshina
- Department of Chemistry University of Southern California Los Angeles CA 90089 USA
- Terahertz Sensing and Imaging Laboratory RIKEN 519-1399 Aramaki-Aoba, Aoba-ku Sendai, Miyagi 980-0845 Japan
| | - Russell Sliter
- Department of Chemistry University of Southern California Los Angeles CA 90089 USA
- KLA-Tencor 1 Technology Drive Milpitas CA 95035 USA
| | - Aakash Ravi
- Department of Chemistry The University of British Columbia Vancouver BC V6T 1Z1 Canada
- Department of Physics Harvard University 17 Oxford Street Cambridge MA 02138 USA
| | - Susumu Kuma
- Department of Chemistry The University of British Columbia Vancouver BC V6T 1Z1 Canada
- Atomic, Molecular & Optical Physics Laboratory RIKEN 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Takamasa Momose
- Department of Chemistry The University of British Columbia Vancouver BC V6T 1Z1 Canada
| | - Andrey F. Vilesov
- Department of Chemistry University of Southern California Los Angeles CA 90089 USA
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7
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Raston PL, Jäger W. Microwave spectroscopy of the seeded binary and ternary clusters CO-(pH2)2, CO-pH2-He, CO-HD, and CO-(oD2)(N=1,2). J Chem Phys 2015; 142:144308. [PMID: 25877579 DOI: 10.1063/1.4917420] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We report the Fourier transform microwave spectra of the a-type J = 1-0 transitions of the binary and ternary CO-(pH2)2, CO-pH2-He, CO-HD, and CO-(oD2)N=1,2 clusters. In addition to the normal isotopologue of CO for all clusters, we observed the transitions of the minor isotopologues, (13)C(16)O, (12)C(18)O, and (13)C(18)O, for CO-(pH2)2 and CO-pH2-He. All transitions lie within 335 MHz of the experimentally or theoretically predicted values. In comparison to previously reported infrared spectra [Moroni et al., J. Chem. Phys. 122, 094314 (2005)], we are able to tentatively determine the vibrational shift for CO-pH2-He, in addition to its b-type J = 1-0 transition frequency. The a-type frequency of CO-pH2-He is similar to that of CO-He2 [Surin et al., Phys. Rev. Lett. 101, 233401 (2008)], suggesting that the pH2 molecule has a strong localizing effect on the He density. Perturbation theory analysis of CO-oD2 reveals that it is approximately T-shaped, with an anisotropy of the intermolecular potential amounting to ∼9 cm(-1).
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Affiliation(s)
- Paul L Raston
- Department of Chemistry, University of Adelaide, SA 5005, Australia
| | - Wolfgang Jäger
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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Zhang XL, Li H, Le Roy RJ, Roy PN. Microwave and infrared spectra of CO–(pH2)2, CO–(oD2)2, and mixed CO–pH2–He trimers. Theor Chem Acc 2014. [DOI: 10.1007/s00214-014-1568-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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9
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Berg M, Accardi A, Paulus B, Schmidt B. Rotationally adiabatic pair interactions of para- and ortho-hydrogen with the halogen molecules F2, Cl2, and Br2. J Chem Phys 2014; 141:074303. [PMID: 25149782 DOI: 10.1063/1.4892599] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The present work is concerned with the weak interactions between hydrogen and halogen molecules, i.e., the interactions of pairs H2-X2 with X = F, Cl, Br, which are dominated by dispersion and quadrupole-quadrupole forces. The global minimum of the four-dimensional (4D) coupled cluster with singles and doubles and perturbative triples (CCSD(T)) pair potentials is always a T shaped structure where H2 acts as the hat of the T, with well depths (De) of 1.3, 2.4, and 3.1 kJ/mol for F2, Cl2, and Br2, respectively. MP2/AVQZ results, in reasonable agreement with CCSD(T) results extrapolated to the basis set limit, are used for detailed scans of the potentials. Due to the large difference in the rotational constants of the monomers, in the adiabatic approximation, one can solve the rotational Schrödinger equation for H2 in the potential of the X2 molecule. This yields effective two-dimensional rotationally adiabatic potential energy surfaces where pH2 and oH2 are point-like particles. These potentials for the H2-X2 complexes have global and local minima for effective linear and T-shaped complexes, respectively, which are separated by 0.4-1.0 kJ/mol, where oH2 binds stronger than pH2 to X2, due to higher alignment to minima structures of the 4D-pair potential. Further, we provide fits of an analytical function to the rotationally adiabatic potentials.
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Affiliation(s)
- Matthias Berg
- Institut für Chemie, Freie Universität Berlin, Takustr. 3, D-14195 Berlin, Germany
| | - Antonio Accardi
- Institut für Chemie, Freie Universität Berlin, Takustr. 3, D-14195 Berlin, Germany
| | - Beate Paulus
- Institut für Chemie, Freie Universität Berlin, Takustr. 3, D-14195 Berlin, Germany
| | - Burkhard Schmidt
- Institut für Mathematik, Freie Universität Berlin, Arnimallee 6, D-14195 Berlin, Germany
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10
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Zeng T, Roy PN. Microscopic molecular superfluid response: theory and simulations. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2014; 77:046601. [PMID: 24647079 DOI: 10.1088/0034-4885/77/4/046601] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Since its discovery in 1938, superfluidity has been the subject of much investigation because it provides a unique example of a macroscopic manifestation of quantum mechanics. About 60 years later, scientists successfully observed this phenomenon in the microscopic world though the spectroscopic Andronikashvili experiment in helium nano-droplets. This reduction of scale suggests that not only helium but also para-H2 (pH2) can be a candidate for superfluidity. This expectation is based on the fact that the smaller number of neighbours and surface effects of a finite-size cluster may hinder solidification and promote a liquid-like phase. The first prediction of superfluidity in pH2 clusters was reported in 1991 based on quantum Monte Carlo simulations. The possible superfluidity of pH2 was later indirectly observed in a spectroscopic Andronikashvili experiment in 2000. Since then, a growing number of studies have appeared, and theoretical simulations have been playing a special role because they help guide and interpret experiments. In this review, we go over the theoretical studies of pH2 superfluid clusters since the experiment of 2000. We provide a historical perspective and introduce the basic theoretical formalism along with key experimental advances. We then present illustrative results of the theoretical studies and comment on the possible future developments in the field. We include sufficient theoretical details such that the review can serve as a guide for newcomers to the field.
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Affiliation(s)
- Tao Zeng
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
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11
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Accardi A, Schmidt B. RETRACTED ARTICLE: Quantum effects on translation and rotation of molecular chlorine in solid para-hydrogen. Mol Phys 2013. [DOI: 10.1080/00268976.2013.868086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Antonio Accardi
- Institut für Chemie, Freie Universität Berlin, Berlin, Germany
| | - Burkhard Schmidt
- Institut für Mathematik, Freie Universität Berlin, Berlin, Germany
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12
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Li H, Zhang XL, Le Roy RJ, Roy PN. Analytic Morse/long-range potential energy surfaces and predicted infrared spectra for CO–H2 dimer and frequency shifts of CO in (para-H2)N N = 1–20 clusters. J Chem Phys 2013; 139:164315. [DOI: 10.1063/1.4826595] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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13
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Fajardo ME. High-Resolution Rovibrational Spectroscopy of Carbon Monoxide Isotopologues Isolated in Solid Parahydrogen. J Phys Chem A 2013; 117:13504-12. [DOI: 10.1021/jp407267u] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mario E. Fajardo
- Air Force Research Laboratory, Munitions
Directorate, Ordnance Division, Energetic Materials Branch, AFRL/RWME, 2306 Perimeter
Road, Eglin Air Force Base, Florida 32542-5910, United States
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14
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Wang L, Xie D, Le Roy RJ, Roy PN. A new six-dimensional potential energy surface for H2–N2O and its adiabatic-hindered-rotor treatment. J Chem Phys 2013; 139:034312. [DOI: 10.1063/1.4813527] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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15
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Hayashi M, Ohshima Y. Sub-Doppler Electronic Spectra of Benzene–(H2)n Complexes. J Phys Chem A 2013; 117:9819-30. [DOI: 10.1021/jp312754v] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Masato Hayashi
- Institute
for Molecular Science, National Institutes of Natural Sciences, Myodaiji,
Okazaki 444-8585, Japan
| | - Yasuhiro Ohshima
- Institute
for Molecular Science, National Institutes of Natural Sciences, Myodaiji,
Okazaki 444-8585, Japan
- SOKENDAI, The Graduate University for Advanced Studies, Okazaki 444-8585, Japan
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16
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Raston PL, Jäger W, Li H, Le Roy RJ, Roy PN. Persistent molecular superfluid response in doped para-hydrogen clusters. PHYSICAL REVIEW LETTERS 2012; 108:253402. [PMID: 23004599 DOI: 10.1103/physrevlett.108.253402] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2011] [Indexed: 06/01/2023]
Abstract
Direct observation of superfluid response in para-hydrogen (p-H(2)) remains a challenge because of the need for a probe that would not induce localization and a resultant reduction in superfluid fraction. Earlier work [H. Li, R. J. Le Roy, P.-N. Roy, and A. R. W. McKellar, Phys. Rev. Lett. 105, 133401 (2010)] has shown that carbon dioxide can probe the effective inertia of p-H(2) although larger clusters show a lower superfluid response due to localization. It is shown here that the lighter carbon monoxide probe molecule allows one to measure the effective inertia of p-H(2) clusters while maintaining a maximum superfluid response with respect to dopant rotation. Microwave spectroscopy and a theoretical analysis based on Feynman path-integral simulations are used to support this conclusion.
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Affiliation(s)
- P L Raston
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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17
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McKellar ARW. Infrared spectra of CO2-doped hydrogen clusters, (H2)N–CO2. J Chem Phys 2012; 136:094305. [DOI: 10.1063/1.3691101] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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18
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Mella M. Higher order diffusion Monte Carlo propagators for linear rotors as diffusion on a sphere: development and application to O2@He(n). J Chem Phys 2011; 135:114504. [PMID: 21950868 DOI: 10.1063/1.3639190] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Exploiting the theoretical treatment of particles diffusing on corrugated surfaces and the isomorphism between the "particle on a sphere" and a linear molecule rotation, a new diffusion kernel is introduced to increase the order of diffusion Monte Carlo (DMC) simulations involving linear rotors. Tests carried out on model systems indicate the superior performances of the new rotational diffusion kernel with respect to the simpler alternatives previously employed. In particular, it is evidenced a second order convergence toward exact results with respect to the time step of dynamical correlation functions, a fact that guarantees an identical order for the diffusion part of the DMC projector. The algorithmic advantages afforded by the latter are discussed, especially with respect to the "a posteriori" and "on the fly" extrapolation schemes. As a first application to the new algorithm, the structure and energetics of O(2)@He(n) (n = 1-40) clusters have been studied. This was done to investigate the possible cause of the quenching of the reaction between O(2) and Mg witnessed upon increasing the size of superfluid He droplets used as a solvent. With the simulations on O(2) indicating a strong localization in the cluster core, the behaviour as a function of n is ascribed to the extremely fluxional comportment of Mg@He(n), which dwells far from the droplet center, albeit being solvated, when n is large.
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Affiliation(s)
- Massimo Mella
- Dipartimento di Scienze Chimiche ed Ambientali, Università degli Studi dell'Insubria, via Lucini 3, 22100 Como, Italy.
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Zeng T, Li H, Le Roy RJ, Roy PN. “Adiabatic-hindered-rotor” treatment of the parahydrogen-water complex. J Chem Phys 2011; 135:094304. [DOI: 10.1063/1.3626840] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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20
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Li H, McKellar ARW, Le Roy RJ, Roy PN. Theoretical and experimental study of weakly bound CO2-(pH2)2 trimers. J Phys Chem A 2011; 115:7327-37. [PMID: 21627164 DOI: 10.1021/jp200810f] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The infrared spectrum of CO(2)-(pH(2))(2) trimers is predicted by performing exact basis-set calculations on a global potential energy surface defined as the sum of accurately known two-body pH(2)-CO(2) (J. Chem. Phys. 2010, 132, 214309) and pH(2)-pH(2) potentials (J. Chem. Phys. 2008, 129, 094304). These results are compared with new spectroscopic measurements for this species, for which 13 transitions are now assigned. A reduced-dimension treatment of the pH(2) rotation has been employed by applying the hindered-rotor averaging technique of Li, Roy, and Le Roy (J. Chem. Phys. 2010, 133, 104305). Three-body effects and the quality of the potential are discussed. A new technique for displaying the three-dimensional pH(2) density in the body-fixed frame is used, and shows that in the ground state the two pH(2) molecules are localized much more closely together than is the case for the two He atoms in the analogous CO(2)-(He)(2) species. A clear tunneling splitting is evident for the torsional motion of the two pH(2) molecules on a ring about the CO(2) molecular axis, in contrast to the case of CO(2)-(He)(2) where a more regular progression of vibrational levels reflects the much lower torsional barrier.
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Affiliation(s)
- Hui Li
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
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21
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Michaud JM, Topic WC, Jäger W. Spectroscopic and Theoretical Study of the Weakly Bound H2−HCCCN Dimer. J Phys Chem A 2011; 115:9456-66. [DOI: 10.1021/jp111812k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Julie M. Michaud
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Wendy C. Topic
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Wolfgang Jäger
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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22
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Mizumoto Y, Ohtsuki Y. Path integral molecular dynamics simulation of quasi-free rotational motion of CO doped in a large para-hydrogen cluster. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2010.11.041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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23
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Li H, Roy PN, Le Roy RJ. An “adiabatic-hindered-rotor” treatment allows para-H2 to be treated as if it were spherical. J Chem Phys 2010; 133:104305. [DOI: 10.1063/1.3476465] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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24
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Li H, Roy PN, Le Roy RJ. Analytic Morse/long-range potential energy surfaces and predicted infrared spectra for CO2–H2. J Chem Phys 2010; 132:214309. [DOI: 10.1063/1.3428619] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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25
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26
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Fajardo ME, Lindsay CM, Momose T. Crystal field theory analysis of rovibrational spectra of carbon monoxide monomers isolated in solid parahydrogen. J Chem Phys 2009; 130:244508. [DOI: 10.1063/1.3158947] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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27
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Zhu H, Xie D. N(2)O in small para-hydrogen clusters: Structures and energetics. J Comput Chem 2009; 30:841-6. [PMID: 19165775 DOI: 10.1002/jcc.21207] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We present the minimum-energy structures and energetics of clusters of the linear N(2)O molecule with small numbers of para-hydrogen molecules with pairwise additive potentials. Interaction energies of (p-H(2))-N(2)O and (p-H(2))-(p-H(2)) complexes were calculated by averaging the corresponding full-dimensional potentials over the H(2) angular coordinates. The averaged (p-H(2))-N(2)O potential has three minima corresponding to the T-shaped and the linear (p-H(2))-ONN and (p-H(2))-NNO structures. Optimization of the minimum-energy structures was performed using a Genetic Algorithm. It was found that p-H(2) molecules fill three solvation rings around the N(2)O axis, each of them containing up to five p-H(2) molecules, followed by accumulation of two p-H(2) molecules at the oxygen and nitrogen ends. The first solvation shell is completed at N = 17. The calculated chemical potential oscillates with cluster size up to the completed first solvation shell. These results are consistent with the available experimental measurements.
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Affiliation(s)
- Hua Zhu
- School of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China.
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28
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Szalewicz K. Interplay between theory and experiment in investigations of molecules embedded in superfluid helium nanodroplets†. INT REV PHYS CHEM 2008. [DOI: 10.1080/01442350801933485] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Patkowski K, Cencek W, Jankowski P, Szalewicz K, Mehl JB, Garberoglio G, Harvey AH. Potential energy surface for interactions between two hydrogen molecules. J Chem Phys 2008; 129:094304. [DOI: 10.1063/1.2975220] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Zhou Y, Ran H, Xie D. A five-dimensional potential energy surface and predicted infrared spectra for the N2O-hydrogen complexes. J Chem Phys 2006; 125:174310. [PMID: 17100442 DOI: 10.1063/1.2363992] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a five-dimensional potential energy surface for the N(2)O-hydrogen complex using supermolecular approach with the full counterpoise correction at the coupled-cluster singles and doubles with noniterative inclusion of connected triple level. The normal mode Q(3) for the nu(3) antisymmetric stretching vibration of the N(2)O molecule was included in the calculations of the potential energies. The radial discrete variable representation/angular finite basis representation method and Lanczos algorithm were employed to calculate the rovibrational energy levels for four species of N(2)O-hydrogen complexes (N(2)O-para-H(2), -ortho-H(2), -ortho-D(2), and -para-D(2)) without separating the inter- and intramolecular vibrations. The calculated band origins are all blueshifted relative to the isolated N(2)O molecule and in good agreement with the experimental values. The calculated rotational spectroscopic constants and molecular structures agree well with the available experimental results. The frequencies and line intensities of the rovibrational transitions in the nu(3) region of N(2)O for the van der Waals ground vibrational state were calculated and compared with the observed spectra. The predicted infrared spectra are consistent with the observed spectra and show that the N(2)O-H(2) complexes are mostly a-type transitions while both a-type and b-type transitions are significant for the N(2)O-D(2) complexes.
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Affiliation(s)
- Yanzi Zhou
- Institute of Theoretical and Computational Chemistry, Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
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Sebastianelli F, Elmatad YS, Jiang H, Bacić Z. HF in clusters of molecular hydrogen: II. Quantum solvation by H2 isotopomers, cluster rigidity, and comparison with CO-doped parahydrogen clusters. J Chem Phys 2006; 125:164313. [PMID: 17092079 DOI: 10.1063/1.2363989] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a comprehensive theoretical study of the quantum solvation of the HF molecule by small clusters of the H2 isotopomers, p-H2, HD, and o-D2, with up to 13 hydrogen solvent molecules. This complements our earlier work on the HF-doped parahydrogen clusters [H. Jiang and Z. Bacic, J. Chem. Phys. 122, 244306 (2005)]. The ground-state properties of the clusters are calculated exactly using the diffusion Monte Carlo method. Detailed information is obtained regarding the size and isotopomer dependences of the energetics, vibrationally averaged structures, and their rigidity. The rigidity of these clusters is investigated further by analyzing the distributions of their principal moments of inertia from the diffusion Monte Carlo simulations. The clusters are found to be rather rigid, especially when compared with the pure parahydrogen clusters of the same size. Extensive comparison is made with the quantum Monte Carlo results for the CO-doped parahydrogen clusters and significant differences are observed in the size evolution of certain properties, notably the chemical potential.
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Paesani F, Whaley KB. Vibrational shifts of OCS in mixed clusters of parahydrogen and helium. J Chem Phys 2006; 124:234310. [PMID: 16821921 DOI: 10.1063/1.2202318] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We present a detailed theoretical study of the solvation structure and solvent induced vibrational shifts for an OCS molecule embedded in pure parahydrogen clusters and in mixed parahydrogen/helium clusters. The use of two recent OCS-(parahydrogen) and OCS-helium ab initio potential energy surfaces having explicit dependence on the asymmetric stretch of the OCS molecule allows calculation of the frequency shift of the OCS nu(3) vibration as a function of the cluster size and composition. We present results for clusters containing up to a full first solvation shell of parahydrogen (N=17 molecules), and up to M=128-N helium atoms. Due to the greater interaction strength of parahydrogen than helium with OCS, in the mixed clusters the parahydrogen molecules always displace He atoms in the first solvation shell around OCS and form multiple axial rings as in the pure parahydrogen clusters. In the pure clusters, the chemical potential of parahydrogen shows several magic numbers (N=8,11,14) that reflect an enhanced stability of axial rings containing one less molecule than required for complete filling at N=17. Only the N=14 magic number survives in the mixed clusters, as a result of different filling orders of the rings and greater delocalization of both components. The OCS vibration shows a redshift in both pure and mixed clusters, with N-dependent values that are in good agreement with the available experimental data. The dependence of the frequency shift on the cluster size and its composition is analyzed in terms of the parahydrogen and helium density distributions around the OCS molecule as a function of N and M. The frequency shift is found to be strongly dependent on the detailed distribution of the parahydrogen molecules in the pure parahydrogen clusters, and to be larger but show a smoother dependence on N in the presence of additional helium, consistent with the more delocalized nature of the mixed clusters.
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Affiliation(s)
- F Paesani
- Department of Chemistry, University of California-Berkeley, Berkeley, CA 94720, USA.
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Paesani F, Whaley * KB. Potential energy surface and infrared spectra of OCS–hydrogen complexes. Mol Phys 2006. [DOI: 10.1080/00268970500224575] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Paolini S, Fantoni S, Moroni S, Baroni S. Computational spectroscopy of helium-solvated molecules: Effective inertia, from small He clusters toward the nanodroplet regime. J Chem Phys 2005; 123:114306. [PMID: 16392558 DOI: 10.1063/1.2032969] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Accurate computer simulations of the rotational dynamics of linear molecules solvated in He clusters indicate that the large-size (nanodroplet) regime is attained quickly for light rotors (HCN) and slowly for heavy ones (OCS, N2O, and CO2), thus challenging previously reported results. Those results spurred the view that the different behavior of light rotors with respect to heavy ones-including a smaller reduction of inertia upon solvation of the former-would result from the lack of adiabatic following of the He density upon molecular rotation. We have performed computer experiments in which the rotational dynamics of OCS and HCN molecules was simulated using a fictitious inertia appropriate to the other molecule. These experiments indicate that the approach to the nanodroplet regime, as well as the reduction of the molecular inertia upon solvation, is determined by the anistropy of the potential, more than by the molecular weight. Our findings are in agreement with recent infrared and/or microwave experimental data which, however, are not yet totally conclusive by themselves.
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Affiliation(s)
- Stefano Paolini
- Scuola Internazionale Superiore di Studi Avanzati and CNR-INFM, DEMOCRITOS National Simulation Center, Trieste, Italy.
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Tang J, McKellar ARW. Infrared spectra of seeded hydrogen clusters: (para-H2)N–N2O and (ortho-H2)N–N2O, N=2–13. J Chem Phys 2005; 123:114314. [PMID: 16392566 DOI: 10.1063/1.2032989] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
High-resolution infrared spectra of clusters containing para-H2 and/or ortho-H2 and a single nitrous oxide molecule are studied in the 2225-cm(-1) region of the upsilon1 fundamental band of N2O. The clusters are formed in pulsed supersonic jet expansions from a cooled nozzle and probed using a tunable infrared diode laser spectrometer. The simple symmetric rotor-type spectra generally show no resolved K structure, with prominent Q-branch features for ortho-H2 but not para-H2 clusters. The observed vibrational shifts and rotational constants are reported. There is no obvious indication of superfluid effects for para-H2 clusters up to N=13. Sharp transitions due to even larger clusters are observed, but no definite assignments are possible. Mixed (para-H2)N-(ortho-H2)M-N2O cluster line positions can be well predicted by linear interpolation between the corresponding transitions of the pure clusters.
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Affiliation(s)
- Jian Tang
- Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario
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Abstract
We introduce a new criterion, based on multipole dynamical correlations calculated within reptation quantum Monte Carlo, to discriminate between a melting versus freezing behavior in quantum clusters. This criterion is applied to small clusters of para-hydrogen molecules (both pristine and doped with a CO chromophore), for cluster sizes of around twelve molecules. This is a magic size at which para-hydrogen clusters display an icosahedral structure and a large stability. Despite the similar geometric structure of CO@(pH2)12 and (pH2)13, the first system has a rigid, crystalline, behavior; the second behaves more like a superfluid (or, possibly, a supersolid).
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Affiliation(s)
- Stefano Baroni
- Scuola Internazionale Superiore di Studi Avanzati SISSA and INFM DEMOCRITOS National Simulation Center, Via Beirut 2-4, 34014 Trieste, Italy.
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