William Smith | University of Guelph (original) (raw)

Papers by William Smith

Research paper thumbnail of Global phase diagrams of binary mixtures Systematic basis for describing types of phase equilibrium phenomena

Journal of the Chemical Society, Faraday Transactions, 1997

Research paper thumbnail of Reference system selection and average Mayer-function perturbation theory for molecular fluids

Faraday Discussions of the Chemical Society, 1978

A perturbation theory for molecular fluids due to Smith, and Perram and White is analysed and equ... more A perturbation theory for molecular fluids due to Smith, and Perram and White is analysed and equations are presented in a computationally convenient form for determining the full angulardependent pair correlation function. The discussion centres on the most appropriate choice of reference system and we use the Mayer function as expansion functional. The implications of the resulting RAM (reference system average Mayer-function expansion) theory are discussed.

Research paper thumbnail of New force fields for aqueous electrolytes using high concentration chemical potential and density data

Research paper thumbnail of Application of molecular simulations: Insight into the liquid bridging and jetting phenomena

Molecular dynamics simulations have been performed on pure liquid water, aqueous solutions of sod... more Molecular dynamics simulations have been performed on pure liquid water, aqueous solutions of sodium chloride, and polymer solutions exposed to a strong external electric field with the goal to gain molecular insight into the structural response to the field. Several simulation methodologies have been used to elucidate the molecular mechanisms of the processes leading to the formation of liquid bridges and jets (in the production of nanofibers). It is shown that in the established nanoscale structures, the molecules form a chain with their dipole moments oriented parallel to the applied field throughout the entire sample volume. The presence of ions may disturb this structure leading to its ultimate disintegration into droplets; the concentration dependence of the threshold field required to stabilize a liquid column has been determined. Conformational changes of the polymer in the jetting process have also been observed.

Research paper thumbnail of Refrigeration cycle design by molecular simulation

Research paper thumbnail of Molecular Based Study of Fluids

Research paper thumbnail of Refrigeration cycle design for refrigerant mixtures by molecular simulation

Collection of Czechoslovak Chemical Communications, 2010

Abstract We describe a molecular simulation methodology to calculate the properties of a vapor-co... more Abstract We describe a molecular simulation methodology to calculate the properties of a vapor-compression refrigeration cycle and its Coefficient of Performance, in the case when the refrigerant is a mixture. The methodology requires only a molecular force-field model for each refrigerant pure component and, for improved accuracy, an expression for the vapor pressure of each pure component as a function of temperature. Both may be constructed by means of theoretical approaches in combination with minimal amounts of experimental ...

Research paper thumbnail of Prediction of isoenthalps, Joule–Thomson Coefficients and Joule–Thomson inversion curves of refrigerants by molecular simulation

Fluid Phase Equilibria, 2014

We describe molecular simulation methodology based on the recently proposed NPH MC algorithm to c... more We describe molecular simulation methodology based on the recently proposed NPH MC algorithm to calculate isoenthalps (HC), Joule-Thomson coefficients, , (JTC) and Joule-Thomson inversion curves (JTIC), and apply it to the representative ethane-based alternative refrigerants R125, R134a and R152a over a wide range of thermodynamic conditions. Although JTIC have been calculated previously by molecular simulation, HC and JTC have rarely been studied by this approach, due to the requirement to incorporate ideal gas specific heat data, c IG p (T ). Traditionally, calculations of HC, JTC and JTIC have been implemented using multi-parameter empirical equations fitted to experimental data. In contrast, molecular simulation methodology requires a force field (FF) describing the molecular interactions, which contains a relatively small number of adjustable parameters. Our study uses FFs from the literature, and c IG p (T ) from a comprehensive compilation based solely on quantum and statistical mechanical calculations. Our simulation results are compared with pseudo-experimental results obtained from the REFPROP software package. We generated results in both single-and two-phase regions, and for thermodynamic conditions outside the range of REFPROP's capabilities. Where both sets of results are available, the simulation results are in good agreement with those of REFPROP. Our studies also suggest that more accurate quantum and statistical mechanical calculations of the refrigerant c IG p (T ), which are feasible with current computer technology, would improve the reliability of both empirically based and molecular simulation calculations of HC and JTC for existing refrigerants, and would also reduce the experimental data requirement for newly proposed candidate refrigerants. Finally, we also compare our results with those from new calculations using two representative cubic equations of state (EOS); they provide reasonable but not quantitatively accurate results, particularly for and the JTIC.

Research paper thumbnail of Vapor−Liquid Equilibria in Five-Site (TIP5P) Models of Water

The Journal of Physical Chemistry B, 2004

Using the Gibbs ensemble Monte Carlo simulations, we have determined vapor-liquid equilibria in a... more Using the Gibbs ensemble Monte Carlo simulations, we have determined vapor-liquid equilibria in a new, reparametrized five-site model (TIP5P-E) of water and compared them with the original TIP5P model of Mahoney and Jorgensen and TIP4P water. It is shown that for vapor-liquid equilibria properties, the new model provides only a marginal improvement over the original model and both models are considerably inferior to the TIP4P model.

Research paper thumbnail of Accurate Computer Simulation of Phase Equilibrium for Complex Fluid Mixtures. Application to Binaries Involving Isobutene, Methanol, Methyl tert -Butyl Ether, and n -Butane

The Journal of Physical Chemistry B, 1999

We have developed a new method, called the reaction Gibbs ensemble Monte Carlo (RGEMC) method, fo... more We have developed a new method, called the reaction Gibbs ensemble Monte Carlo (RGEMC) method, for the computer simulation of the phase equilibria for multicomponent mixtures, given an intermolecular potential model for the constituent molecular species. The approach treats the phase equilibrium conditions as a special type of chemical reaction and incorporates knowledge of the pure-substance vapor pressure data into the simulations. Unlike macroscopic thermodynamic-based approaches like the Wilson and the universal quasichemical functional group activity coefficients (UNIFAC) approximations, no experimental information concerning the mixtures is required. In addition to the PTxy phase equilibrium data, the volumetric properties of the mixture are calculated. We developed intermolecular potential models based on the optimized potentials for liquid simulations (OPLS) of Jorgensen and used the RGEMC method to predict phase equilibrium data for the binary systems isobutene + methyl tert-butyl ether (MTBE) and the binaries formed by methanol with isobutene, MTBE, and n-butane. The predictions are excellent, and of comparable accuracy to those obtained using the Wilson and the UNIFAC thermodynamic-based approaches, even though such approaches use experimental mixture information.

Research paper thumbnail of Global phase diagrams of model and real binary fluid mixtures Part II. Non-Lorentz–Berthelot mixtures of attractive hard spheres

Physical Chemistry Chemical Physics, 1999

the mixture exhibits a rich set of low-temperature azeotropic phenomena: cusps on the pÈT project... more the mixture exhibits a rich set of low-temperature azeotropic phenomena: cusps on the pÈT projections of 1.15, azeotropic lines, exchange of branches of azeotropic lines, zero-temperature limited azeotropy, and double critical azeotropic points. Some of these azeotropic phenomena are described here for the Ðrst time.

Research paper thumbnail of Computationally efficient Monte Carlo simulations for polarisable models: multi-particle move method for water and aqueous electrolytes

We demonstrate improved computational efficiencies of Monte Carlo (MC) simulations for polarisabl... more We demonstrate improved computational efficiencies of Monte Carlo (MC) simulations for polarisable force fields by implementing the multi-particle-move MC (MPM-MC) method [Moučka F, Rouha M, Nezbeda I. Efficient multiparticle sampling in Monte Carlo simulations on fluids: application to polarizable models. J Phys Chem. 2007;126:224106]. Force bias and smart alternatives along with the Ewald summation and generalised reaction field have been considered and tested for both pure polarisable water models and polarisable aqueous electrolytes. For water, we consider the recently developed Baranyai -Kiss force field [A transferable classical potential for the water molecule. J Chem Phys. 2010;133:144109] and the SWM4-DP force field of Lamoureux et al. [A simple polarizable model of water based on classical Drude oscillators. J Chem Phys. 2003;119:5185], and for electrolytes the polarisable AH/SWM4-DP force field associated with the SWM4-DP solvent. These force fields incorporate polarisability as a charge-on-spring model, and the Baranyai -Kiss model incorporates charges in the form of a Gaussian distribution instead of point charges. For neat water, in addition to calculating the standard thermodynamic properties and water structure and comparing our results with those obtained from standard molecular dynamics simulations, we also investigate its vapour-liquid equilibrium properties. For aqueous electrolyte solutions, we study NaCl at ambient conditions and calculate its density and chemical potential as a function of concentration, representing apparently the first such simulation results using these polarisable models at finite concentrations. Our results demonstrate that MC simulations can be efficiently performed on polarisable models if the MPM method is incorporated.

Research paper thumbnail of Monte Carlo simulation results for the full pair correlation function of the hard dumbell fluid

Molecular Physics, 1981

An ultimate goal of the equilibrium statistical mechanical study of molecular fluids is the deter... more An ultimate goal of the equilibrium statistical mechanical study of molecular fluids is the determination of the full pair correlation'function g =g(R, f~), since this function provides complete information on the system. However, this is not a simple task, since g is a function of at least five variables (in the case of linear molecules) and it is therefore practically impossible to determine it completely, even by computer simulation.

Research paper thumbnail of Computer simulation studies of molecular fluid mixtures

Molecular Physics, 1985

The average site-site correlation functions, G αβ, and site-centred spherical harmonic expansion ... more The average site-site correlation functions, G αβ, and site-centred spherical harmonic expansion coefficients, G αβ, 100, of heteronuclear hard dumbells and linear symmetric fused-hard-sphere triatomics, and of equimolar mixtures of these fluids with hard spheres and with each other have been calculated by means of the Monte Carlo simulation method. The pressure of the systems have been evaluated using the contact values of G αβ and G αβ, 100, and compared with a semi-empirical equation of state of Boublik and Nezbeda, ...

Research paper thumbnail of The site-site pair correlation functions of molecular fluids

Molecular Physics, 1984

Calculations are performed using the RAM perturbation theory for heteronuclear hard-sphere diatom... more Calculations are performed using the RAM perturbation theory for heteronuclear hard-sphere diatomics, and compared with those obtained from RISM theory. Calculations are made to first order in the RAM theory employing three different intermolecular coordinate systems, as well using a mixture reference system suggested in part I of this series. The mixture reference system produces uniformly poor results. If a coordinate system is chosen in which reference points are placed at the molecular centres of mass, good results are ...

Research paper thumbnail of Perturbation theories for molecular fluids

Molecular Physics, 1982

The RAM perturbation theory is considered for the hard spherocylinder fluid. It is shown that, by... more The RAM perturbation theory is considered for the hard spherocylinder fluid. It is shown that, by using a reduced form of the theory proposed by Melnyk and Smith excellent results are obtained for the pair correlation function, its spherical harmonic coefficients, and the equation of state. This agreement holds over a wide range of spherocylinder length-to-breadth ratios.

Research paper thumbnail of Conjectures on fluids of hard spherocylinders, dumbells, and spheres

Molecular Physics, 1979

There has been much recent interest in hard spherocylinders and hard dumbells as simple models of... more There has been much recent interest in hard spherocylinders and hard dumbells as simple models of molecular fluids, from the theoretical [1-6], experimental [7, 8](using computer simulations), and semi-empirical [9-12] viewpoints. Since the experimental computer simulation results are widely used to test theories, it is useful to examine them critically from as many different viewpoints as possible. In this note, on the basis of several known facts, we discuss two conjectures concerning the equation of state of these fluids. We then ...

Research paper thumbnail of Theory of the glass transition and the amorphous state

Molecular Physics, 1992

A thermodynamically-based criterion for the location of the glass transition in the system of har... more A thermodynamically-based criterion for the location of the glass transition in the system of hard spheres is proposed and its structural consequences are investigated. By re-analyzing existing computer simulation data and theoretical results, we estimate the hard-sphere glass transition reduced density to be ρg≅ 0· 965, corresponding to a reduced pressure β P≅ 13· 11. The capability of the Ornstein-Zernike integral equation to describe the structure and thermodynamics of both the supercooled liquid and amorphous solid and the glass ...

Research paper thumbnail of Monte Carlo study of hard-body fluids at a hard wall: pure fluids and mixtures of spheres, heteronuclear dumbbells and linear triatomics

Molecular Physics, 1990

Pure fluids of hard heteronuclear dumbbells and linear symetric triatomics, and binary mixtures o... more Pure fluids of hard heteronuclear dumbbells and linear symetric triatomics, and binary mixtures of these fluids with hard spheres at a hard structureless wall, are studied by Monte Carlo simulations. In addition to density profiles (angle-averaged wall/site pair correlation functions) of all atomic sites in each molecule, the average number density of sites in the first layer, and radial slices through the full one-particle correlation function of triatomics, are also calculated. Different patterns of packing of the dumbbells and triatomics in the mixtures ...

Research paper thumbnail of The site-site correlation functions of molecular fluids

Molecular Physics, 1982

We present results for the site-site pair correlation functions of a wide range of site interacti... more We present results for the site-site pair correlation functions of a wide range of site interaction molecular fluid models for which computer simulation data are available. The calculations are obtained via zeroth order RAM perturbation theory using a site-centred molecular coordinate system. For homonuclear diatomics, both of hardsphere and Lennard-Jones type, our results are excellent. For heteronuclear diatomics and triatomics, the results range from excellent to poor. Possible means of improving the results in the latter cases ...

Research paper thumbnail of Global phase diagrams of binary mixtures Systematic basis for describing types of phase equilibrium phenomena

Journal of the Chemical Society, Faraday Transactions, 1997

Research paper thumbnail of Reference system selection and average Mayer-function perturbation theory for molecular fluids

Faraday Discussions of the Chemical Society, 1978

A perturbation theory for molecular fluids due to Smith, and Perram and White is analysed and equ... more A perturbation theory for molecular fluids due to Smith, and Perram and White is analysed and equations are presented in a computationally convenient form for determining the full angulardependent pair correlation function. The discussion centres on the most appropriate choice of reference system and we use the Mayer function as expansion functional. The implications of the resulting RAM (reference system average Mayer-function expansion) theory are discussed.

Research paper thumbnail of New force fields for aqueous electrolytes using high concentration chemical potential and density data

Research paper thumbnail of Application of molecular simulations: Insight into the liquid bridging and jetting phenomena

Molecular dynamics simulations have been performed on pure liquid water, aqueous solutions of sod... more Molecular dynamics simulations have been performed on pure liquid water, aqueous solutions of sodium chloride, and polymer solutions exposed to a strong external electric field with the goal to gain molecular insight into the structural response to the field. Several simulation methodologies have been used to elucidate the molecular mechanisms of the processes leading to the formation of liquid bridges and jets (in the production of nanofibers). It is shown that in the established nanoscale structures, the molecules form a chain with their dipole moments oriented parallel to the applied field throughout the entire sample volume. The presence of ions may disturb this structure leading to its ultimate disintegration into droplets; the concentration dependence of the threshold field required to stabilize a liquid column has been determined. Conformational changes of the polymer in the jetting process have also been observed.

Research paper thumbnail of Refrigeration cycle design by molecular simulation

Research paper thumbnail of Molecular Based Study of Fluids

Research paper thumbnail of Refrigeration cycle design for refrigerant mixtures by molecular simulation

Collection of Czechoslovak Chemical Communications, 2010

Abstract We describe a molecular simulation methodology to calculate the properties of a vapor-co... more Abstract We describe a molecular simulation methodology to calculate the properties of a vapor-compression refrigeration cycle and its Coefficient of Performance, in the case when the refrigerant is a mixture. The methodology requires only a molecular force-field model for each refrigerant pure component and, for improved accuracy, an expression for the vapor pressure of each pure component as a function of temperature. Both may be constructed by means of theoretical approaches in combination with minimal amounts of experimental ...

Research paper thumbnail of Prediction of isoenthalps, Joule–Thomson Coefficients and Joule–Thomson inversion curves of refrigerants by molecular simulation

Fluid Phase Equilibria, 2014

We describe molecular simulation methodology based on the recently proposed NPH MC algorithm to c... more We describe molecular simulation methodology based on the recently proposed NPH MC algorithm to calculate isoenthalps (HC), Joule-Thomson coefficients, , (JTC) and Joule-Thomson inversion curves (JTIC), and apply it to the representative ethane-based alternative refrigerants R125, R134a and R152a over a wide range of thermodynamic conditions. Although JTIC have been calculated previously by molecular simulation, HC and JTC have rarely been studied by this approach, due to the requirement to incorporate ideal gas specific heat data, c IG p (T ). Traditionally, calculations of HC, JTC and JTIC have been implemented using multi-parameter empirical equations fitted to experimental data. In contrast, molecular simulation methodology requires a force field (FF) describing the molecular interactions, which contains a relatively small number of adjustable parameters. Our study uses FFs from the literature, and c IG p (T ) from a comprehensive compilation based solely on quantum and statistical mechanical calculations. Our simulation results are compared with pseudo-experimental results obtained from the REFPROP software package. We generated results in both single-and two-phase regions, and for thermodynamic conditions outside the range of REFPROP's capabilities. Where both sets of results are available, the simulation results are in good agreement with those of REFPROP. Our studies also suggest that more accurate quantum and statistical mechanical calculations of the refrigerant c IG p (T ), which are feasible with current computer technology, would improve the reliability of both empirically based and molecular simulation calculations of HC and JTC for existing refrigerants, and would also reduce the experimental data requirement for newly proposed candidate refrigerants. Finally, we also compare our results with those from new calculations using two representative cubic equations of state (EOS); they provide reasonable but not quantitatively accurate results, particularly for and the JTIC.

Research paper thumbnail of Vapor−Liquid Equilibria in Five-Site (TIP5P) Models of Water

The Journal of Physical Chemistry B, 2004

Using the Gibbs ensemble Monte Carlo simulations, we have determined vapor-liquid equilibria in a... more Using the Gibbs ensemble Monte Carlo simulations, we have determined vapor-liquid equilibria in a new, reparametrized five-site model (TIP5P-E) of water and compared them with the original TIP5P model of Mahoney and Jorgensen and TIP4P water. It is shown that for vapor-liquid equilibria properties, the new model provides only a marginal improvement over the original model and both models are considerably inferior to the TIP4P model.

Research paper thumbnail of Accurate Computer Simulation of Phase Equilibrium for Complex Fluid Mixtures. Application to Binaries Involving Isobutene, Methanol, Methyl tert -Butyl Ether, and n -Butane

The Journal of Physical Chemistry B, 1999

We have developed a new method, called the reaction Gibbs ensemble Monte Carlo (RGEMC) method, fo... more We have developed a new method, called the reaction Gibbs ensemble Monte Carlo (RGEMC) method, for the computer simulation of the phase equilibria for multicomponent mixtures, given an intermolecular potential model for the constituent molecular species. The approach treats the phase equilibrium conditions as a special type of chemical reaction and incorporates knowledge of the pure-substance vapor pressure data into the simulations. Unlike macroscopic thermodynamic-based approaches like the Wilson and the universal quasichemical functional group activity coefficients (UNIFAC) approximations, no experimental information concerning the mixtures is required. In addition to the PTxy phase equilibrium data, the volumetric properties of the mixture are calculated. We developed intermolecular potential models based on the optimized potentials for liquid simulations (OPLS) of Jorgensen and used the RGEMC method to predict phase equilibrium data for the binary systems isobutene + methyl tert-butyl ether (MTBE) and the binaries formed by methanol with isobutene, MTBE, and n-butane. The predictions are excellent, and of comparable accuracy to those obtained using the Wilson and the UNIFAC thermodynamic-based approaches, even though such approaches use experimental mixture information.

Research paper thumbnail of Global phase diagrams of model and real binary fluid mixtures Part II. Non-Lorentz–Berthelot mixtures of attractive hard spheres

Physical Chemistry Chemical Physics, 1999

the mixture exhibits a rich set of low-temperature azeotropic phenomena: cusps on the pÈT project... more the mixture exhibits a rich set of low-temperature azeotropic phenomena: cusps on the pÈT projections of 1.15, azeotropic lines, exchange of branches of azeotropic lines, zero-temperature limited azeotropy, and double critical azeotropic points. Some of these azeotropic phenomena are described here for the Ðrst time.

Research paper thumbnail of Computationally efficient Monte Carlo simulations for polarisable models: multi-particle move method for water and aqueous electrolytes

We demonstrate improved computational efficiencies of Monte Carlo (MC) simulations for polarisabl... more We demonstrate improved computational efficiencies of Monte Carlo (MC) simulations for polarisable force fields by implementing the multi-particle-move MC (MPM-MC) method [Moučka F, Rouha M, Nezbeda I. Efficient multiparticle sampling in Monte Carlo simulations on fluids: application to polarizable models. J Phys Chem. 2007;126:224106]. Force bias and smart alternatives along with the Ewald summation and generalised reaction field have been considered and tested for both pure polarisable water models and polarisable aqueous electrolytes. For water, we consider the recently developed Baranyai -Kiss force field [A transferable classical potential for the water molecule. J Chem Phys. 2010;133:144109] and the SWM4-DP force field of Lamoureux et al. [A simple polarizable model of water based on classical Drude oscillators. J Chem Phys. 2003;119:5185], and for electrolytes the polarisable AH/SWM4-DP force field associated with the SWM4-DP solvent. These force fields incorporate polarisability as a charge-on-spring model, and the Baranyai -Kiss model incorporates charges in the form of a Gaussian distribution instead of point charges. For neat water, in addition to calculating the standard thermodynamic properties and water structure and comparing our results with those obtained from standard molecular dynamics simulations, we also investigate its vapour-liquid equilibrium properties. For aqueous electrolyte solutions, we study NaCl at ambient conditions and calculate its density and chemical potential as a function of concentration, representing apparently the first such simulation results using these polarisable models at finite concentrations. Our results demonstrate that MC simulations can be efficiently performed on polarisable models if the MPM method is incorporated.

Research paper thumbnail of Monte Carlo simulation results for the full pair correlation function of the hard dumbell fluid

Molecular Physics, 1981

An ultimate goal of the equilibrium statistical mechanical study of molecular fluids is the deter... more An ultimate goal of the equilibrium statistical mechanical study of molecular fluids is the determination of the full pair correlation'function g =g(R, f~), since this function provides complete information on the system. However, this is not a simple task, since g is a function of at least five variables (in the case of linear molecules) and it is therefore practically impossible to determine it completely, even by computer simulation.

Research paper thumbnail of Computer simulation studies of molecular fluid mixtures

Molecular Physics, 1985

The average site-site correlation functions, G αβ, and site-centred spherical harmonic expansion ... more The average site-site correlation functions, G αβ, and site-centred spherical harmonic expansion coefficients, G αβ, 100, of heteronuclear hard dumbells and linear symmetric fused-hard-sphere triatomics, and of equimolar mixtures of these fluids with hard spheres and with each other have been calculated by means of the Monte Carlo simulation method. The pressure of the systems have been evaluated using the contact values of G αβ and G αβ, 100, and compared with a semi-empirical equation of state of Boublik and Nezbeda, ...

Research paper thumbnail of The site-site pair correlation functions of molecular fluids

Molecular Physics, 1984

Calculations are performed using the RAM perturbation theory for heteronuclear hard-sphere diatom... more Calculations are performed using the RAM perturbation theory for heteronuclear hard-sphere diatomics, and compared with those obtained from RISM theory. Calculations are made to first order in the RAM theory employing three different intermolecular coordinate systems, as well using a mixture reference system suggested in part I of this series. The mixture reference system produces uniformly poor results. If a coordinate system is chosen in which reference points are placed at the molecular centres of mass, good results are ...

Research paper thumbnail of Perturbation theories for molecular fluids

Molecular Physics, 1982

The RAM perturbation theory is considered for the hard spherocylinder fluid. It is shown that, by... more The RAM perturbation theory is considered for the hard spherocylinder fluid. It is shown that, by using a reduced form of the theory proposed by Melnyk and Smith excellent results are obtained for the pair correlation function, its spherical harmonic coefficients, and the equation of state. This agreement holds over a wide range of spherocylinder length-to-breadth ratios.

Research paper thumbnail of Conjectures on fluids of hard spherocylinders, dumbells, and spheres

Molecular Physics, 1979

There has been much recent interest in hard spherocylinders and hard dumbells as simple models of... more There has been much recent interest in hard spherocylinders and hard dumbells as simple models of molecular fluids, from the theoretical [1-6], experimental [7, 8](using computer simulations), and semi-empirical [9-12] viewpoints. Since the experimental computer simulation results are widely used to test theories, it is useful to examine them critically from as many different viewpoints as possible. In this note, on the basis of several known facts, we discuss two conjectures concerning the equation of state of these fluids. We then ...

Research paper thumbnail of Theory of the glass transition and the amorphous state

Molecular Physics, 1992

A thermodynamically-based criterion for the location of the glass transition in the system of har... more A thermodynamically-based criterion for the location of the glass transition in the system of hard spheres is proposed and its structural consequences are investigated. By re-analyzing existing computer simulation data and theoretical results, we estimate the hard-sphere glass transition reduced density to be ρg≅ 0· 965, corresponding to a reduced pressure β P≅ 13· 11. The capability of the Ornstein-Zernike integral equation to describe the structure and thermodynamics of both the supercooled liquid and amorphous solid and the glass ...

Research paper thumbnail of Monte Carlo study of hard-body fluids at a hard wall: pure fluids and mixtures of spheres, heteronuclear dumbbells and linear triatomics

Molecular Physics, 1990

Pure fluids of hard heteronuclear dumbbells and linear symetric triatomics, and binary mixtures o... more Pure fluids of hard heteronuclear dumbbells and linear symetric triatomics, and binary mixtures of these fluids with hard spheres at a hard structureless wall, are studied by Monte Carlo simulations. In addition to density profiles (angle-averaged wall/site pair correlation functions) of all atomic sites in each molecule, the average number density of sites in the first layer, and radial slices through the full one-particle correlation function of triatomics, are also calculated. Different patterns of packing of the dumbbells and triatomics in the mixtures ...

Research paper thumbnail of The site-site correlation functions of molecular fluids

Molecular Physics, 1982

We present results for the site-site pair correlation functions of a wide range of site interacti... more We present results for the site-site pair correlation functions of a wide range of site interaction molecular fluid models for which computer simulation data are available. The calculations are obtained via zeroth order RAM perturbation theory using a site-centred molecular coordinate system. For homonuclear diatomics, both of hardsphere and Lennard-Jones type, our results are excellent. For heteronuclear diatomics and triatomics, the results range from excellent to poor. Possible means of improving the results in the latter cases ...