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Besnard M, Cabaço MI, Coutinho JAP, Danten Y. Assessing the non-ideality of the CO2-CS2 system at molecular level: a Raman scattering study. J Chem Phys 2013; 139:124504. [PMID: 24089783 DOI: 10.1063/1.4821593] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The dense phase of CO2-CS2 mixtures has been analysed by Raman spectroscopy as a function of the CO2 concentration (0.02-0.95 mole fractions) by varying the pressure (0.5 MPa up to 7.7 MPa) at constant temperature (313 K). The polarised and depolarised spectra of the induced (ν2, ν3) modes of CS2 and of the ν1-2ν2 Fermi resonance dyad of both CO2 and CS2 have been measured. Upon dilution with CO2, the evolution of the spectroscopic observables of all these modes displays a "plateau-like" region in the CO2 mole fraction 0.3-0.7 never previously observed in CO2-organic liquids mixtures. The bandshape and intensity of the induced modes of CS2 are similar to those of pure CS2 up to equimolar concentration, after which variations occur. The preservation of the local ordering from pure CS2 to equimolar concentration together with the non-linear evolution of the spectroscopic observables allows inferring that two solvation regimes exist with a transition occurring in the plateau domain. In the first regime, corresponding to CS2 concentrated mixtures, the liquid phase is segregated with dominant CS2 clusters, whereas, in the second one, CO2 monomers and dimers and CO2-CS2 hetero-dimers coexist dynamically on a picosecond time-scale. It is demonstrated that the subtle interplay between attractive and repulsive interactions which provides a molecular interpretation of the non-ideality of the CO2-CS2 mixture allows rationalizing the volume expansion and the existence of the plateau-like region observed in the pressure-composition diagram previously ascribed to the proximity of an upper critical solution temperature at lower temperatures.
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Affiliation(s)
- M Besnard
- Institut des Sciences Moléculaires, CNRS (UMR 5255), Université Bordeaux 1, 351 Cours de la Libération, 33405 Talence Cedex, France
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Singh A, Gangopadhyay D, Popp J, Singh RK. Effect of deuteration on hydrogen bonding: a comparative concentration dependent Raman and DFT study of pyridine in CH₃OH and CD₃OD and pyrimidine in H₂O and D₂O. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2012; 99:136-143. [PMID: 23063856 DOI: 10.1016/j.saa.2012.09.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 08/30/2012] [Accepted: 09/09/2012] [Indexed: 06/01/2023]
Abstract
The relative effect of hydrogen bonding of pyrimidine (Pyr) in H(2)O/D(2)O and pyridine (Py) in CH(3)OH/CD(3)OD has been analyzed using Raman Difference Spectroscopic (RDS) technique and DFT calculations. This study is focused on analyzing the concentration dependent variation of linewidth, peak position and intensity of ring breathing mode of Py and Pyr. The ring breathing mode of Pyr in H(2)O and D(2)O has three components; due to free Pyr, lighter complexes of mPyr+nH(2)O/D(2)O and heavier complexes of mPyr+nH(2)O/D(2)O. The pyridine molecules, however, show only two components in CH(3)OH and CD(3)OD. Of these two components, one corresponds to free Py and the other inhomogeneously broadened profile corresponds to all mPy+nCH(3)OH/CD(3)OD complexes. The variation of peak position and linewidth establishes the role of dipole moment of complexes and the diffusion in the mixture. In case of CD(3)OD solution splitting was observed in ∼1030 cm(-1) band of Py, where an additional band at ∼1034 cm(-1) appears at x(Py) ≤ 0.4. However, this band remains single at all concentrations in case of CH(3)OH solvent.
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Affiliation(s)
- Anurag Singh
- Department of Physics, Banaras Hindu University, Varanasi 221 005, India
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Howard AA, Tschumper GS, Hammer NI. Effects of Hydrogen Bonding on Vibrational Normal Modes of Pyrimidine. J Phys Chem A 2010; 114:6803-10. [DOI: 10.1021/jp101267w] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Austin A. Howard
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677
| | - Gregory S. Tschumper
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677
| | - Nathan I. Hammer
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677
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Lomas JS, Maurel F. Water and alcohol(s): what's the difference? A proton NMR and DFT study of hetero-association with pyridine. J PHYS ORG CHEM 2008. [DOI: 10.1002/poc.1351] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Srivastava SK, Ojha AK, Kiefer W, Asthana BP. Investigation of nu(N-H) and nu(C-N) stretching modes of propylamine (C3H7NH2) in a binary system C3H7NH2 + CH3OH via concentration dependent Raman study and ab initio calculations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2005; 61:2832-9. [PMID: 16165021 DOI: 10.1016/j.saa.2004.10.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2004] [Accepted: 10/27/2004] [Indexed: 05/04/2023]
Abstract
Raman spectra of propylamine (C3H7NH2) and its binary mixtures, C3H7NH2 + CH3OH with varying mole fractions of the reference system, C3H7NH2, C were recorded in two widely apart wavenumber regions, 3100-3600 cm(-1) and 1225-1325 cm(-1). In the former region, the two Raman bands at approximately 3305 and approximately 3326 cm(-1), obtained after the line shape analysis, which were assigned to symmetric nu(N-H) and anti-symmetric nu(N-H) stretching modes, respectively, show a downshift upon dilution. However, whereas the nu(N-H) anti-symmetric mode shows a shift of 18.6 cm(-1), the nu(N-H) symmetric mode shows a much smaller shift (5.7 cm(-1)) between neat liquid and high dilution, C = 0.1. This aspect has been explained using the optimized geometries calculated employing ab initio theory (MP2 level) for the neat C3H7NH2 and its different hydrogen-bonded complexes. The linewidth versus concentration plot for the nu(N-H) anti-symmetric stretching mode, however exhibits a distinct maxima at C = 0.4, which has been explained as a slight departure from the concentration fluctuation model. In the latter region, a symmetric peak is observed, which corresponds to nu(C-N) stretching mode, which shows an upshift upon dilution and an almost linear concentration dependence. This has also been explained in terms of the parameters obtained from the optimized geometries of the different hydrogen-bonded complexes.
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Affiliation(s)
- Sunil K Srivastava
- Laser and Spectroscopy Laboratory, Department of Physics, Banaras Hindu University, Varanasi 221005, India
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Oparin R, Tassaing T, Danten Y, Besnard M. A vibrational spectroscopic study of structure evolution of water dissolved in supercritical carbon dioxide under isobaric heating. J Chem Phys 2004; 120:10691-8. [PMID: 15268095 DOI: 10.1063/1.1739214] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A combination of Raman scattering spectroscopy and infrared absorption was applied to investigate the structural evolution of water dissolved in supercritical carbon dioxide under isobaric heating (T=40-340 degrees C, P=250 bar). Quantitative analysis of experimental spectra allowed us to determine that at relatively moderate temperatures water dissolved in CO(2)-rich phase exists only under monomeric form (solitary water surrounding by CO(2) molecules), but hydrogen-bonded species, namely, dimers, begin to appear upon heating. At the same time, the ratio of dimers to monomers concentration increases with further temperature increase and at temperatures close to the temperature of total miscibility of the mixture (T=366 degrees C, P=250 bar), water dimers only are present in the CO(2)-rich phase.
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Affiliation(s)
- R Oparin
- Laboratoire de Physico-Chimie Moléculaire, CNRS (UMR 5803), Université Bordeaux I, 351 Cours de la Libération, 33405 Talence Cedex, France
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Schlücker S, Singh RK, Asthana BP, Popp J, Kiefer W. Hydrogen-Bonded Pyridine−Water Complexes Studied by Density Functional Theory and Raman Spectroscopy. J Phys Chem A 2001. [DOI: 10.1021/jp0122272] [Citation(s) in RCA: 140] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- S. Schlücker
- Institut für Physikalische Chemie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, and Laser and Spectroscopy Laboratory, Department of Physics, Banaras Hindu University, Varanasi 221 005, India
| | - Ranjan K. Singh
- Institut für Physikalische Chemie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, and Laser and Spectroscopy Laboratory, Department of Physics, Banaras Hindu University, Varanasi 221 005, India
| | - B. P. Asthana
- Institut für Physikalische Chemie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, and Laser and Spectroscopy Laboratory, Department of Physics, Banaras Hindu University, Varanasi 221 005, India
| | - J. Popp
- Institut für Physikalische Chemie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, and Laser and Spectroscopy Laboratory, Department of Physics, Banaras Hindu University, Varanasi 221 005, India
| | - W. Kiefer
- Institut für Physikalische Chemie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, and Laser and Spectroscopy Laboratory, Department of Physics, Banaras Hindu University, Varanasi 221 005, India
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Singh RK, Asthana B, Verma A, Pathak C. Raman study of the concentration dependence of the frequency shifts and linewidth changes in a(3Cl-pyridine + methanol) system. Chem Phys Lett 1997. [DOI: 10.1016/s0009-2614(97)00960-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Tassaing T, Besnard M, Yarwood J. Far IR vibrational spectroscopic studies of the chemical dynamics of the pyridine/iodine system in solution. Chem Phys Lett 1997. [DOI: 10.1016/s0009-2614(97)00149-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Ferwerda R, van der Maas J, van Duijneveldt F. Pyridine adsorption onto metal oxides: an ab initio study of model systems. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/1381-1169(95)00179-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Symons MC. Comment on “The evolution between slow and rapid chemical exchange processes in a liquid binary mixture”. Chem Phys Lett 1993. [DOI: 10.1016/0009-2614(93)87189-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Reply to comment on “The evolution between slow and rapid chemical exchange processes in a liquid binary mixture”. Chem Phys Lett 1993. [DOI: 10.1016/0009-2614(93)87190-e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Besnard M, Cabaqo MI, Yarwood J. The evolution between slow and rapid chemical exchange processes in a liquid binary mixture. Chem Phys Lett 1992. [DOI: 10.1016/0009-2614(92)90073-v] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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