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Sadeghi S, Nemati-Kande E. Calculation of the Transport and Relaxation Properties of the Ar···HCl van der Waals Complex Using a New Potential Energy Surface: Comparison of the Classical and Full Quantum Mechanical Kinetic Theory Results with Molecular Dynamics Simulations. J Phys Chem A 2023; 127:1053-1067. [PMID: 36652600 DOI: 10.1021/acs.jpca.2c05901] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The intermolecular potential energy surface (PES) of the Ar···HCl complex was calculated at the RCCSD(T)/aug-cc-pvQz-BF level of theory. The obtained potential was expanded in terms of Legendre polynomials and fitted to a mathematical model. The fitting results are highly correlated with the ab initio PES data with SD = 5.9 × 10-3 cm-1 and average absolute deviation (AAD) = 4.0 × 10-6 cm-1. The interaction second virial coefficients (B12) in the temperature range of 190-480 K were calculated by considering classical and first quantum corrections and compared with the available experimental data. A reasonable agreement with the experimental and calculated B12 was obtained. The PES was also used to obtain the rovibrational energy levels, and the spectroscopic rovibrational constants were obtained. It was found that the D0 values differ ∼2.25 cm-1 from the experimental values of the ground rovibrational state. Furthermore, the obtained potential was used to calculate the transport and relaxation properties using full quantum close-coupling (CC) formalism and the classical kinetic theory methods based on the Mason-Monchik approximation (MMA). It was found that the deviation between MMA and CC calculations is increased with increasing the temperature due to the higher influence of the rotational degrees of freedom on the transport properties. Also, the contribution of the inelastic (off-diagonal) transitions for diffusion coefficient is higher than the viscosity. Furthermore, the classical molecular dynamics simulations were performed using LJ(12,6) and Vashishta models, to calculate the interaction diffusion and viscosity coefficients, and compared with the results of the full quantum CC calculations. The obtained results confirm that the Vashishta model is better fitted to the ab initio potentials and is more accurate than LJ(12,6) in calculation of the diffusion coefficients.
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Affiliation(s)
- Salar Sadeghi
- Department of Physical Chemistry, Chemistry Faculty, Urmia University, Urmia57179-44514, Iran
| | - Ebrahim Nemati-Kande
- Department of Physical Chemistry, Chemistry Faculty, Urmia University, Urmia57179-44514, Iran
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Ng Pack G, Rotondaro MC, Shah PP, Mandal A, Erramilli S, Ziegler LD. Two-dimensional infrared spectroscopy from the gas to liquid phase: density dependent J-scrambling, vibrational relaxation, and the onset of liquid character. Phys Chem Chem Phys 2019; 21:21249-21261. [PMID: 31538165 DOI: 10.1039/c9cp04101j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ultrafast 2DIR spectra and pump-probe responses of the N2O ν3 asymmetric stretch in SF6 as a function of density from the gas to supercritical phase and liquid are reported. 2DIR spectra unequivocally reveal free rotor character at all densities studied in the gas and supercritical region. Analysis of the 2DIR spectra determines that J-scrambling or rotational relaxation in N2O is highly efficient, occurring in ∼1.5 to ∼2 collisions with SF6 at all non-liquid densities. In contrast, N2O ν3 vibrational energy relaxation requires ∼15 collisions, and complete vibrational equilibrium occurs on the ∼ns scale at all densities. An independent binary collision model is sufficient to describe these supercritical state point dynamics. The N2O ν3 in liquid SF6 2DIR spectrum shows no evidence of free rotor character or spectral diffusion. Using these 2DIR results, hindered rotor or liquid-like character is found in gas and all supercritical solutions for SF6 densities ≥ρ* = 0.3, and increases with SF6 density. 2DIR spectral analysis offers direct time domain evidence of critical slowing for SF6 solutions closest to the critical point density. Applications of 2DIR to other high density and supercritical solution dynamics and descriptions are discussed.
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Affiliation(s)
- Greg Ng Pack
- Department of Chemistry, Boston University, Boston, MA 02215, USA. and Photonics Center, Boston University, Boston, MA 02215, USA
| | - Matthew C Rotondaro
- Department of Chemistry, Boston University, Boston, MA 02215, USA. and Photonics Center, Boston University, Boston, MA 02215, USA
| | - Parth P Shah
- Department of Chemistry, Boston University, Boston, MA 02215, USA. and Photonics Center, Boston University, Boston, MA 02215, USA
| | - Aritra Mandal
- Department of Chemistry, University of Colorado, Boulder, CO 80309, USA
| | - Shyamsunder Erramilli
- Photonics Center, Boston University, Boston, MA 02215, USA and Department of Physics, Boston University, Boston, MA 02215, USA
| | - L D Ziegler
- Department of Chemistry, Boston University, Boston, MA 02215, USA. and Photonics Center, Boston University, Boston, MA 02215, USA
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Tran H, Li G, Ebert V, Hartmann JM. Super- and sub-Lorentzian effects in the Ar-broadened line wings of HCl gas. J Chem Phys 2017; 146:194305. [PMID: 28527465 DOI: 10.1063/1.4983397] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Using previously recorded spectra of HCl diluted in Ar gas at room temperature for several pressure conditions, we show that the absorptions in between successive P and R transitions are significantly different from those predicted using purely Lorentzian line shapes. Direct theoretical predictions of the spectra are also made using requantized classical molecular dynamics simulations and an input HCl-Ar interaction potential. They provide the time evolution of the dipole auto-correlation function (DAF) whose Fourier-Laplace transform yields the absorption spectrum. These calculations very well reproduce the observed super-Lorentzian behavior in the troughs between the intense lines in the central part of the band and the tendency of absorption to become sub-Lorentzian in the band wings between high J lines. The analysis shows that the former behavior is essentially due to incomplete collisions which govern the DAF at very short times. In addition, the increasing influence of line-mixing when going away from the band center explains the tendency of absorption to become more and more sub-Lorentzian in the wings.
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Affiliation(s)
- Ha Tran
- Laboratoire de Météorologie Dynamique, IPSL, CNRS, Sorbonne Universités, UPMC University Paris 06, 75252 Paris, France
| | - Gang Li
- Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany
| | - Volker Ebert
- Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany
| | - Jean-Michel Hartmann
- Laboratoire de Météorologie Dynamque, IPSL, CNRS, Ecole Polytechnique, Université Paris-Saclay, 91128 Palaiseau, France
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Padilla A, Pérez J. Mixed classical quantum dynamical simulation of mid-infrared Q branch of HCl diluted in Ar. J Mol Liq 2014. [DOI: 10.1016/j.molliq.2014.04.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Jain A, Sibert EL. Vibrational relaxation of chloroiodomethane in cold argon. J Chem Phys 2013; 139:144312. [PMID: 24116624 DOI: 10.1063/1.4823837] [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
Electronically exciting the C-I stretch in the molecule chloroiodomethane CH2ClI embedded in a matrix of argon at 12 K can lead to an isomer, iso-chloroiodomethane CH2Cl-I, that features a chlorine iodine bond. By temporally probing the isomer at two different frequencies of 435 nm and 485 nm, multiple timescales for isomerization and vibrational energy relaxation were inferred [T. J. Preston, et al., J. Chem. Phys. 135, 114503 (2011)]. This relaxation is studied theoretically using molecular dynamics by considering 2 and 3 dimensional models. Multiple decay rate constants of the same order of magnitude as the experiment are observed. These decay rate constants are interpreted within the context of the Landau-Teller theory. Sensitivity of the decay rate constants on the bath and system parameters shed more light into the mechanism of vibrational energy relaxation.
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Affiliation(s)
- Amber Jain
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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Padilla A, Pérez J. Non-Markovian near-infrared Q branch of HCl diluted in liquid Ar. J Chem Phys 2013; 139:084505. [DOI: 10.1063/1.4818993] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Abou-Chahine F, Greaves SJ, Dunning GT, Orr-Ewing AJ, Greetham GM, Clark IP, Towrie M. Vibrationally resolved dynamics of the reaction of Cl atoms with 2,3-dimethylbut-2-ene in chlorinated solvents. Chem Sci 2013. [DOI: 10.1039/c2sc21267f] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Padilla A, Pérez J, Herrebout W, Van der Veken B, Bulanin M. A simulation study of the vibration–rotational spectra of HCl diluted in Ar: Rotational dynamics and the origin of the Q-branch. J Mol Struct 2010. [DOI: 10.1016/j.molstruc.2009.09.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Medina A, Roco JMM, Hernández AC, Velasco S. Dynamical characterization of rotationally hindered species in liquids. J Chem Phys 2005; 123:234509. [PMID: 16392933 DOI: 10.1063/1.2137699] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The rotational dynamics of HCl in liquid Ar has been studied by means of molecular-dynamics simulations. We calculate the lifetimes of weakly bound HCl-Ar dimers induced by the anisotropic pair interaction. It is shown that, although lifetimes are small with respect to the reorientational decorrelation, the time interval between the breaking down and formation of the next dimer is negligibly small. Thus, with respect to the rotational dynamics of the probe, the effect is similar to that and eventually would cause a time-stable complex. This provokes a peculiar hindered rotation of the diatomic in the liquid which is macroscopically embodied in the infrared spectrum of the solution as a Q-branch nonexistent otherwise.
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Affiliation(s)
- A Medina
- Departamento de Física Aplicada, Facultad de Ciencias, Universidad de Salamanca, 37008 Salamanca, Spain.
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Pérez J, Padilla A, Herrebout WA, Van der Veken BJ, Hernández AC, Bulanin MO. Experimental analysis and modified rotor description of the infrared fundamental band of HCl in Ar, Kr, and Xe solutions. J Chem Phys 2005; 122:194507. [PMID: 16161597 DOI: 10.1063/1.1902925] [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
We report an experimental study of the rotovibrational fundamental PQR-band shapes in the IR absorption spectra of HCl dissolved in condensed rare gases in a wide range of temperatures. The effective vibrational frequencies are determined from analysis of the fine rotational structure partially resolved in the band wings. The central Q-branch components appear redshifted with respect to the effective vibrational frequencies, their shifts in different solvents found to match the HCl stretching mode shifts in binary Rg...HCl van der Waals heterodimers. Theoretical quasi-free rotor and modified rotor models are applied to describe evolution of the band profiles at changing thermodynamic conditions. Both models are shown to reproduce equally well the observed spectral density distributions in the band wings. However, the modified rotor formalism that accounts for depopulation of the lower-energy rotational solute states provides better agreement with the experiment in the range of the P- and R-branch maxima. We surmise that the Q branches separated from the measured spectral profiles are formed by transitions between rotationally hindered states of diatomic molecules coupled to the solvent by the local anisotropy of the interaction potential.
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Affiliation(s)
- J Pérez
- Departamento de Física Fundamental y Experimental Electrónica y Sistemas, Universidad de La Laguna, 38204 Tenerife, Spain.
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Kandratsenka A, Schroeder J, Schwarzer D, Vikhrenko VS. Molecular dynamics modeling of cooling of vibrationally highly excited carbon dioxide produced in the photodissociation of organic peroxides in solution. Phys Chem Chem Phys 2005; 7:1205-13. [DOI: 10.1039/b414623a] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Medina A, Roco JMM, Calvo Hernández A, Velasco S. Infrared spectral profiles in liquids and atom-diatom interactions. J Chem Phys 2004; 121:6353-60. [PMID: 15446932 DOI: 10.1063/1.1789937] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Molecular dynamics simulations of the infrared spectrum of a generic simple polar diatomic in a liquid nonpolar solvent allow to reproduce the different prototypical experimental line shapes of this kind of systems. This is feasible by using different solute-solvent anisotropic potentials at fixed thermodynamic conditions. In the limit cases, the rotation of the diatomic is explained in terms of a quasifree motion or a rotational diffusion evolution and the spectra show a doublet structure formed by P and R branches or a unique collapsed branch, respectively. When the profile contains three branches, including an intense Q branch in the vicinity of the center of the band, rotational evolution presents a particular hindering that can be understood by studying the influence on rotational spectral densities of the different time scales involved in rotational relaxation. Cancellation/enhancement effects among spectral density terms arising from intermediate and long times (0.4-1 ps) are essential to understand rotational hindering.
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Affiliation(s)
- A Medina
- Departamento de Fisica Aplicada, Facultad de Ciencias, Universidad de Salamanca, 37008 Salamanca, Spain.
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Tscherbul T. State-to-state rate constants for rotational relaxation of CO in collisions with Ar: a quantum study. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.06.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Pérez J, Padilla A, Bulanin MO, Domanskaya AV, Kerl K. A study of molecular rotation in dense fluids from the first vibrational overtone band shape of HCl in Xe fluid. Phys Chem Chem Phys 2004. [DOI: 10.1039/b313308g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Medina A, Roco JMM, Calvo Hernández A, Velasco S. InfraredQ-branch absorption and rotationally-hindered species in liquids. J Chem Phys 2003. [DOI: 10.1063/1.1597478] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Bulanin MO, Kerl K, Padilla A, Hernández AC, Pérez J. Infrared fundamental bandshape of HCl in fluid SF6: A modified-rotor description. Phys Chem Chem Phys 2003. [DOI: 10.1039/b209043k] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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