Oxygen-18 isotope effects in the liquid water–pyridine system as a probe of intermolecular forces

Oxygen-18 exchange between gaseous carbon dioxide and water in liquid water–pyridine mixtures is used as a probe for changes in intermolecular forces when the composition of the system is changed from pure water to pure pyridine. In agreement with results obtained previously by other methods, it is found that the interaction energy of an 'average' water molecule with the medium decreases when the mole fraction of pyridine is varied from zero to unity. The experimental results are related to the vapour pressure isotope effect, P(H218O)/P(H216O), of the binary mixtures. The utility of the Stern – Van Hook – Wolfsberg equation for vapour pressure isotope effects has been investigated. In addition, a plot of the equilibrium constant of the oxygen-18 exchange reaction vs. the mole fraction of pyridine presents no evidence of the formation of stoichiometric pyridine–water complexes.

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Phase equilibrium for ozone-containing hydrates formed from an (ozone+oxygen) gas mixture coexisting with gaseous carbon dioxide and liquid water

The Journal of Chemical Thermodynamics ◽

10.1016/j.jct.2012.01.009 ◽

2012 ◽

Vol 49 ◽

pp. 1-6 ◽

Cited By ~ 12

Author(s):

Sanehiro Muromachi ◽

Ryo Ohmura ◽

Yasuhiko H. Mori

Keyword(s):

Carbon Dioxide ◽

Phase Equilibrium ◽

Liquid Water ◽

Gas Mixture ◽

Gaseous Carbon Dioxide ◽

Oxygen Gas

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Solubility of carbon dioxide in liquid water and of water in gaseous carbon dioxide in the range 0.2-5 MPa and at temperatures up to 473 K

Journal of Chemical & Engineering Data ◽

10.1021/je00026a012 ◽

1981 ◽

Vol 26 (4) ◽

pp. 388-391 ◽

Cited By ~ 116

Author(s):

Andrzej Zawisza ◽

Boguslawa Malesinska

Keyword(s):

Carbon Dioxide ◽

Liquid Water ◽

Gaseous Carbon Dioxide

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THE VAPOUR PRESSURE OF SOLUTIONS OF CARBON DIOXIDE IN DIFLUORODICHLOROMETHANE

Canadian Journal of Research ◽

10.1139/cjr46b-039 ◽

1946 ◽

Vol 24b (6) ◽

pp. 292-296 ◽

Cited By ~ 5

Author(s):

A. R. Gordon ◽

E. A. MacWilliam

Keyword(s):

Carbon Dioxide ◽

Mole Fraction ◽

Vapour Pressure

The vapour pressure of solutions of carbon dioxide in Freon has been determined at 10° and 20 °C. for pressures up to 25 atm. At both temperatures, the vapour pressure is roughly linear in the mole fraction of carbon dioxide, the deviations being positive for solutions low in carbon dioxide and negative for solutions high in carbon dioxide; for a given concentration, the deviation becomes more negative the higher the temperature.

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On the relation between isotope effects on vapour pressure and molecular structure

Journal de Chimie Physique ◽

10.1051/jcp/1963600052 ◽

1963 ◽

Vol 60 ◽

pp. 52-55

Author(s):

István Kiss ◽

Lajos Matus ◽

István Opauszky

Keyword(s):

Molecular Structure ◽

Vapour Pressure ◽

Isotope Effects

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Generalized self-consistent reaction field theory in a multicenter-multipole ab-initio LCGO framework. I. Electronic properties of the water molecule in a Monte Carlo sample of liquid water molecules studied with standard basis sets

Journal de Chimie Physique ◽

10.1051/jcp/1990870875 ◽

1990 ◽

Vol 87 ◽

pp. 875-903 ◽

Cited By ~ 28

Author(s):

O Tapia ◽

F Colonna ◽

JG Angyan

Keyword(s):

Field Theory ◽

Monte Carlo ◽

Water Molecule ◽

Ab Initio ◽

Electronic Properties ◽

Liquid Water ◽

Basis Sets ◽

Water Molecules ◽

Reaction Field ◽

Self Consistent

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Vapour Pressure Isotope Eﬀect on Evaporation from Pure Organic Phases - a PIMD Approach

10.26434/chemrxiv.12003186.v1 ◽

2020 ◽

Author(s):

Luis Vasquez ◽

Agnieszka Dybala-Defratyka

Keyword(s):

Path Integral ◽

Vapour Pressure ◽

Density Functional ◽

Isotope Effects ◽

Tight Binding ◽

Decomposition Analysis ◽

Energy Decomposition Analysis ◽

Special Importance ◽

Non Covalent Interactions ◽

Covalent Interactions

Very often in order to understand physical and chemical processes taking place among several phases fractionation of naturally abundant isotopes is monitored. Its measurement can be accompanied by theoretical determination to provide a more insightful interpretation of observed phenomena. Predictions are challenging due to the complexity of the effects involved in fractionation such as solvent effects and non-covalent interactions governing the behavior of the system which results in the necessity of using large models of those systems. This is sometimes a bottleneck and limits the theoretical description to only a few methods. In this work vapour pressure isotope effects on evaporation from various organic solvents (ethanol, bromobenzene, dibromomethane, and trichloromethane) in the pure phase are estimated by combining force field or self-consistent charge density-functional tight-binding (SCC-DFTB) atomistic simulations with path integral principle. Furthermore, the recently developed Suzuki-Chin path integral is tested. In general, isotope effects are predicted qualitatively for most of the cases, however, the distinction between position-specific isotope effects observed for ethanol was only reproduced by SCC-DFTB, which indicates the importance of using non-harmonic bond approximations. Energy decomposition analysis performed using the symmetry-adapted perturbation theory (SAPT) revealed sometimes quite substantial differences in interaction energy depending on whether the studied system was treated classically or quantum mechanically. Those observed differences might be the source of different magnitudes of isotope effects predicted using these two different levels of theory which is of special importance for the systems governed by non-covalent interactions.

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