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Mitra S, Sharma VK, Mukhopadhyay R. Diffusion of confined fluids in microporous zeolites and clay materials. Rep Prog Phys 2021; 84:066501. [PMID: 33740783 DOI: 10.1088/1361-6633/abf085] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 03/19/2021] [Indexed: 06/12/2023]
Abstract
Fluids exhibit remarkable variation in their structural and dynamic properties when they are confined at the nanoscopic scale. Various factors, including geometric restriction, the size and shape of the guest molecules, the topology of the host, and guest-host interactions, are responsible for the alterations in these properties. Due to their porous structures, aluminosilicates provide a suitable host system for studying the diffusion of sorbates in confinement. Zeolites and clays are two classes of the aluminosilicate family, comprising very ordered porous or layered structures. Zeolitic materials are important due to their high catalytic activity and molecular sieving properties. Guest molecules adsorbed by zeolites display many interesting features including unidimensional diffusion, non-isotropic rotation, preferred orientation and levitation effects, depending on the guest and host characteristics. These are useful for the separation of hydrocarbons which commonly exist as mixtures in nature. Similarly, clay materials have found application in catalysis, desalination, enhanced oil recovery, and isolation barriers used in radioactive waste disposal. It has been shown that the bonding interactions, level of hydration, interlayer spacing, and number of charge-balancing cations are the important factors that determine the nature of diffusion of water molecules in clays. Here, we present a review of the current status of the diffusion mechanisms of various adsorbed species in different microporous zeolites and clays, as investigated using quasielastic neutron scattering and classical molecular dynamics simulation techniques. It is impossible to write an exhaustive review of the subject matter, as it has been explored over several decades and involves many research topics. However, an effort is made to cover the relevant issues specific to the dynamics of different molecules in microporous zeolites and clay materials and to highlight a variety of interesting features that are important for both practical applications and fundamental aspects.
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Affiliation(s)
- S Mitra
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India
| | - V K Sharma
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India
| | - R Mukhopadhyay
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India
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Sun P, Chen J, Zai S, Gao S, Weng X, Wu Z. Regeneration mechanism of a deactivated zeolite-supported catalyst for the combustion of chlorinated volatile organic compounds. Catal Sci Technol 2021. [DOI: 10.1039/d0cy01060j] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Industrial catalysis is confronted with the common problem of catalyst deactivation.
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Affiliation(s)
- Pengfei Sun
- Department of Environmental Engineering
- Zhejiang University
- Hangzhou
- P. R. China
- Zhejiang Provincial Engineering Research Centre of Industrial Boiler & Furnace Flue Gas Pollution Control
| | - Jingkun Chen
- Department of Environmental Engineering
- Zhejiang University
- Hangzhou
- P. R. China
| | - Shuaiying Zai
- Department of Environmental Engineering
- Zhejiang University
- Hangzhou
- P. R. China
| | - Shan Gao
- Department of Environmental Engineering
- Zhejiang University
- Hangzhou
- P. R. China
- Zhejiang Provincial Engineering Research Centre of Industrial Boiler & Furnace Flue Gas Pollution Control
| | - Xiaole Weng
- Department of Environmental Engineering
- Zhejiang University
- Hangzhou
- P. R. China
- Zhejiang Provincial Engineering Research Centre of Industrial Boiler & Furnace Flue Gas Pollution Control
| | - Zhongbiao Wu
- Department of Environmental Engineering
- Zhejiang University
- Hangzhou
- P. R. China
- Zhejiang Provincial Engineering Research Centre of Industrial Boiler & Furnace Flue Gas Pollution Control
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Dhiman I, Shrestha U, Bhowmik D, Cole D, Gautam S. Influence of molecular shape on self-diffusion under severe confinement: A molecular dynamics study. Chem Phys 2019. [DOI: 10.1016/j.chemphys.2018.08.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Magatani Y, Kuwahara Y, Nishizawa K, Yamashita H. Dramatically Enhanced Phenol Degradation on Alkali Cation-Anchored TiO2
/SiO2
Hybrids: Effect of Cation-π Interaction as a Diffusion-Controlling Tool in Heterogeneous Catalysis. ChemistrySelect 2017. [DOI: 10.1002/slct.201700708] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yasuhiro Magatani
- Division of Materials and Manufacturing Science; Graduate School of Engineering; Osaka University, 2-1 Yamadaoka, Suita; Osaka 565-0871 Japan
| | - Yasutaka Kuwahara
- Division of Materials and Manufacturing Science; Graduate School of Engineering; Osaka University, 2-1 Yamadaoka, Suita; Osaka 565-0871 Japan
- Unit of Elements Strategy Initiative for Catalysts & Batteries (ESICB); Kyoto University, Katsura; Kyoto 615-8520 Japan
| | - Kazuto Nishizawa
- Division of Materials and Manufacturing Science; Graduate School of Engineering; Osaka University, 2-1 Yamadaoka, Suita; Osaka 565-0871 Japan
| | - Hiromi Yamashita
- Division of Materials and Manufacturing Science; Graduate School of Engineering; Osaka University, 2-1 Yamadaoka, Suita; Osaka 565-0871 Japan
- Unit of Elements Strategy Initiative for Catalysts & Batteries (ESICB); Kyoto University, Katsura; Kyoto 615-8520 Japan
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Sahasrabudhe A, Varma S, Gupta NM. The Temperature-Dependent Adsorption Behaviour of Benzene Molecules in ZSM-5 Zeolite Pores: TPD and FT-IR Spectroscopy Studies. ADSORPT SCI TECHNOL 2016. [DOI: 10.1260/0263617054037808] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Temperature-programmed desorption (TPD) and in situ Fourier-transform infrared (FT-IR) spectroscopic methods were employed to investigate the effect of loading and sample temperature on the state of benzene molecules inside the channels of NaZSM-5 zeolite. TPD profiles revealed the existence of at least three distinct states of benzene adsorption, characterized by desorption peak maxima at ca. 120°C, 170°C and 220°C, respectively. Based on the growth behaviour of these bands, it is suggested that the benzene molecules occupy sinusoidal channels, straight channels and external surfaces, in that order. A reverse trend was observed during the subsequent flushing of the sample at varying temperatures. A virtually fixed amount of benzene was occluded at these three locations, depending upon the loading. The FT-IR studies revealed that the benzene molecule exists in a compressed state in the zeolitic channels, with the molecular clusters formed in the process dispersing only at temperatures above 150°C. For initial benzene loadings of up to ca. 1.5 molecules/unit cell, the spectrum obtained showed that in the O—H stretch region the bridge-bonded OH groups and hydroxyl groups associated with the internal zeolitic channels were perturbed simultaneously. The results show that even for a loading lower than necessary for saturation, a considerable amount of benzene remains condensed at the external surface of ZSM-5 zeolite.
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Affiliation(s)
- Arati Sahasrabudhe
- Applied Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085, India
| | - Salil Varma
- Applied Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085, India
| | - Narendra M. Gupta
- Applied Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085, India
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Mukherjee R, De S. Novel carbon-nanoparticle polysulfone hollow fiber mixed matrix ultrafiltration membrane: Adsorptive removal of benzene, phenol and toluene from aqueous solution. Sep Purif Technol 2016. [DOI: 10.1016/j.seppur.2015.11.015] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Mitra S, Sharma V, Chaplot S, Mukhopadhyay R. Diffusion of hydrocarbon in zeolite and effect due to pore topology: Neutron scattering and MD simulation studies. Chem Phys 2014. [DOI: 10.1016/j.chemphys.2013.12.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Ballandras A, Weber G, Paulin C, Bellat JP, Rotger M. Communication: Evidence of structural phase transitions in silicalite-1 by infrared spectroscopy. J Chem Phys 2013; 139:091103. [DOI: 10.1063/1.4819080] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Sharma VK, Gautam S, Mitra S, Mukhopadhyay R. Dynamics of Propylene adsorbed in Na-Y and Na-ZSM5 Zeolites: A QENS and MD Simulation Study. ACTA ACUST UNITED AC 2010. [DOI: 10.1524/zpch.2010.6096] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Here we report dynamics of propylene (smallest asymmetric hydrocarbon) adsorbed in two different host systems – Na-Y and Na-ZSM5 zeolites as studied by quasielastic neutron scattering (QENS) techniques and molecular dynamics (MD) simulation techniques. MD simulation studies suggested that the rotational motion of propylene is much faster than the translation. Therefore, two different spectrometers were used to determine the translational and rotational contributions. Analysis of the QENS data (ΔE~200 μeV) revealed that the translational motion of propylene in Na-ZSM5 zeolite is a factor of 3 slower than that in Na-Y zeolite. This is consistent with the smaller void volume available in Na-ZSM5 zeolite as also the fact that the adsorption of propylene is stronger in Na-ZSM5 as compared to that in Na-Y zeolite as indicated in the Fourier Transformed Infra Red (FTIR) studies. This result is further corroborated by the MD simulation studies. It was found that the translation motion occurs at three time scales in both the systems, only one of which corresponds to that observed through the QENS measurements. To probe the faster rotational motion experiments were carried out on a Triple axis spectrometer with wider energy window (ΔE~3meV). The variation of the elastic incoherent structure factor (EISF) suggests that the observed QE broadening corresponds to isotropic rotational motion of propylene in both the hosts. Rotational diffusion coefficients of propylene molecules are found to be of the same order in both zeolites. Trajectories obtained from MD simulation corresponding to the rotational motion revealed that although on a large time scale, the rotation appears isotropic, but at short time scales the channel structure of the Na-ZSM5 restrict the rotation of propylene molecules. This is in contrast with propylene adsorbed in Na-Y zeolite where rotation remains isotropic even at short time scale. A comparison with other hydrocarbon-zeolite systems as studied by us is also presented here.
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Sharma VK, Gautam S, Mitra S, Rao MN, Tripathi AK, Chaplot SL, Mukhopadhyay R. Dynamics of Adsorbed Hydrocarbon in Nanoporous Zeolite Framework. J Phys Chem B 2009; 113:8066-72. [DOI: 10.1021/jp9014405] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- V. K. Sharma
- Solid State Physics Division, Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | - S. Gautam
- Solid State Physics Division, Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | - S. Mitra
- Solid State Physics Division, Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | - Mala N. Rao
- Solid State Physics Division, Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | - A. K. Tripathi
- Solid State Physics Division, Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | - S. L. Chaplot
- Solid State Physics Division, Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | - R. Mukhopadhyay
- Solid State Physics Division, Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
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Gautam S, Mitra S, Chaplot SL, Mukhopadhyay R. Dynamics of 1,3-butadiene adsorbed in Na-Y zeolite: a molecular dynamics simulation study. Phys Rev E Stat Nonlin Soft Matter Phys 2008; 77:061201. [PMID: 18643250 DOI: 10.1103/physreve.77.061201] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2008] [Indexed: 05/26/2023]
Abstract
Here we report dynamics of 1,3-butadiene molecules adsorbed in Na-Y zeolite as studied using molecular dynamics (MD) simulations. The results showed that the translational motion of the guest molecule exists in three different time scales one of which matches well with the quasielastic neutron scattering (QENS) measurement reported earlier. The translational motion in the component, which has been measured by QENS, is found to occur through discrete jumps, in agreement with the analysis of the experiments. The diffusion coefficients obtained from the correlation functions are compared to those obtained earlier for other hydrocarbons in Na-Y zeolite from MD simulation studies. The diffusion of 1,3-butadiene is found to be slower than that of acetylene but faster than that of propane. The rotational motion is found to be isotropic in nature. Rotational diffusion coefficient of 1,3-butadiene is found to be smaller than that of propane in Na-Y as expected due to the larger inertia of the former.
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Affiliation(s)
- Siddharth Gautam
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai, India
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Gautam S, Mitra S, Sayeed A, Yashonath S, Chaplot S, Mukhopadhyay R. Diffusion of 1,3-butadiene adsorbed in Na–Y zeolite: Neutron scattering study. Chem Phys Lett 2007. [DOI: 10.1016/j.cplett.2007.05.109] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Gautam S, Mitra S, Mukhopadhyay R, Chaplot SL. Diffusion of acetylene inside Na-Y zeolite: molecular dynamics simulation studies. Phys Rev E Stat Nonlin Soft Matter Phys 2006; 74:041202. [PMID: 17155046 DOI: 10.1103/physreve.74.041202] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2006] [Indexed: 05/12/2023]
Abstract
Dynamics of acetylene molecules adsorbed in Na-Y zeolite cages is investigated using molecular dynamics simulation. The translational motion of the acetylene molecules is shown to involve three different time scales. "Free particle" type diffusion is observed in short time and small length scale. At long time and large length scale, center of mass motion of acetylene is determined by the zeolitic pore topology. Rotational motion of the acetylene is found to be very fast. Detailed analysis of the intermediate scattering function corresponding to the rotational motion showed large-angle jumps that could be described by an m-diffusion model.
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Affiliation(s)
- Siddharth Gautam
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
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Gupta NM, Kumar D, Kamble VS, Mitra S, Mukhopadhyay R, Kartha VB. Fourier Transform Infrared and Quasielectron Neutron Scattering Studies on the Binding Modes of Methanol Molecules in the Confined Spaces of HMCM-41 and HZSM-5: Role of Pore Structure and Surface Acid Sites. J Phys Chem B 2006; 110:4815-23. [PMID: 16526719 DOI: 10.1021/jp053668e] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Quasielastic neutron scattering (QENS) and Fourier transform infrared spectroscopic studies were carried out on methanol molecules adsorbed in HMCM-41 and HZSM-5 molecular sieves to monitor the effect of pore structure on their occluded state under the conditions of ambient temperature and 5-250 mbar pressures. The QENS results have shown that the pore geometry of the host matrix and the dipolar character of the adsorbate are together responsible for the binding state of guest molecules in the confining medium. Thus, neither translational nor free rotational motion was noticed for methanol molecules adsorbed in HZSM-5, in contrast to benzene and cyclohexane molecules of almost similar size that are reported to undergo a rotational motion under the identical conditions of loading (Phys. Chem. Chem. Phys. 2001, 3, 4449; 2003, 5, 3066). In the case of HMCM-41, a translational motion of occluded methanol molecules was clearly observed with a diffusion constant D approximately 1.5 x 10(-5) cm2 s(-1), as compared to a value of D approximately 2.6 x 10(-5) cm2 s(-1) for its liquid state. These results indicate that the adsorbed methanol experiences a considerable extent of supercooling due to capillary condensation in zeolitic pores, giving rise to formation of a metastable state even at room temperature. In HZSM-5, entrapped methanol exists in an almost solidlike state, whereas in HMCM-41, its density lies between that of the solid and the liquid phases. Infrared spectroscopic study conducted using deuterium-labeled adsorbate and host matrixes have given evidence for different kinds of interactions between the methanol molecules and the host matrix, depending upon the loading. For small loadings the internal hydroxy groups within the pore system get perturbed first, giving rise to formation of the methoxy groups. Multilayer adsorption and capillary condensation of methanol occur for a loading of 0.05 mmol per gram and above, within the pore system and also at the external surface, giving rise to a highly compressed state due to strong intermolecular bonding. At the same time, a considerable amount of exchange occurred between the hydroxy groups of the adsorbed methanol and those of the host matrix. Such exchange of hydroxy groups may play an important role in the catalytic properties of the porous aluminosilicates.
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Affiliation(s)
- Narendra M Gupta
- Applied Chemistry and Solid State Physics Divisions, Bhabha Atomic Research Centre, Trombay, Mumbai - 400 085.
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Bertrand O, Weber G, Maure S, Bernardet V, Bellat JP, Paulin C. Spectroscopic Signatures of VOC Physisorption on Microporous Solids. Application for Trichloroethylene and Tetrachloroethylene Adsorption on MFI Zeolites. J Phys Chem B 2005; 109:13312-21. [PMID: 16852661 DOI: 10.1021/jp048442a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This paper presents an experimental infrared spectroscopic study of the physisorption of trichloroethylene (TCE) and tetrachloroethylene (PCE) on a self-supported high silica ZSM5 zeolite. The evolution of the shape, area, and location of vibration bands of both the adsorbent and the adsorbate is analyzed with respect to the number of sorbed molecules. The state of the adsorbed phase is characterized upon adsorption by comparing the location of the investigated vibration bands with the location of the corresponding vibration bands of the chloroalkenes in gaseous, liquid, and solid phases. The singular behavior of PCE with respect to TCE is seen from the modification of vibration bands of both the adsorbed phase and the adsorbent upon loading. The adsorption process proceeds by stages for PCE, whereas it appears continuous for TCE. Particular micropore loadings are evidenced at 4 and 6.5 molec.uc(-1) for PCE and at 6 molec.uc(-1) for TCE, in agreement with previous macroscopic and microscopic data. In addition, the presence of admolecules induces at least one emerging vibration band located at around 1715 cm(-1), mainly due to a contribution of the microporous surface of the adsorbent.
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Affiliation(s)
- O Bertrand
- Laboratoire de Recherches sur la Réactivité des Solides, UMR 5613, 9, avenue Alain Savary - B. P. 47870-21078 DIJON Cedex, France.
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Sivasankar N, Vasudevan S. Temperature-Programmed Desorption and Infrared Spectroscopic Studies of Benzene Adsorption in Zeolite ZSM-5. J Phys Chem B 2004. [DOI: 10.1021/jp048399r] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- N. Sivasankar
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 566012, India
| | - S. Vasudevan
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 566012, India
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Mukhopadhyay R, Sayeed A, Rao MN, Anilkumar A, Mitra S, Yashonath S, Chaplot S. Rotation of propane molecules in supercages of Na–Y zeolite. Chem Phys 2003. [DOI: 10.1016/s0301-0104(03)00082-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Mukhopadhyay R, Sayeed A, Mitra S, Anil Kumar AV, Rao MN, Yashonath S, Chaplot SL. Rotational dynamics of propane in Na-Y zeolite: a molecular dynamics and quasielastic neutron-scattering study. Phys Rev E Stat Nonlin Soft Matter Phys 2002; 66:061201. [PMID: 12513271 DOI: 10.1103/physreve.66.061201] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2002] [Indexed: 05/24/2023]
Abstract
We report results from molecular dynamics (MD) simulations and quasielastic neutron-scattering (QENS) measurements on the rotational dynamics of propane in Na-Y zeolite at room temperature with a loading of four molecules per alpha cage. Rotational part of the intermediate scattering function F(Q,t) obtained from the MD simulation suggests that rotational motion is faster relative to the translational motion. Various rotational models fitted to the MD data suggest that rotation is isotropic. It is found that the hydrogen atoms lie, on the average, on a sphere of radius 1.88+/-0.05 A, which is also the average distance of the hydrogen atoms from the center of mass of the propane molecule. Results from QENS measurements are in excellent agreement with those obtained from MD, suggesting that the intermolecular potential employed in the MD simulation provides a realistic description of propane motion within faujasite. The rotational diffusion constant D(R) is 1.05+/-0.09 x 10(12) sec(-1) from the QENS data, which may be compared with that obtained from the MD data (0.82+/-0.05 x 10(12) sec(-1)).
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Affiliation(s)
- R Mukhopadhyay
- Solid State Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India.
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Sahasrabudhe A, Mitra S, Tripathi AK, Mukhopadhyay R, Gupta NM. Fourier Transform Infrared and Quasi-Elastic Neutron Scattering Investigations on the Binding States and the Dynamics of Benzene Molecules in the Pores of MCM-41 Molecular Sieves. J Phys Chem B 2002. [DOI: 10.1021/jp021545d] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- A. Sahasrabudhe
- Applied Chemistry Division and Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | - S. Mitra
- Applied Chemistry Division and Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | - A. K. Tripathi
- Applied Chemistry Division and Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | - R. Mukhopadhyay
- Applied Chemistry Division and Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
| | - N. M. Gupta
- Applied Chemistry Division and Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085, India
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