@article {2418,
	title = {Vapour-liquid phase transition of dipolar particles},
	journal = {Molecular Physics},
	volume = {107},
	number = {4-6},
	year = {2009},
	note = {ISI Document Delivery No.: 448EATimes Cited: 5Cited Reference Count: 54Ganzenmueller, Georg Patey, G. N. Camp, Philip J.},
	pages = {403-413},
	type = {Article},
	abstract = {The question of whether a vapour-liquid phase transition exists in systems of particles with purely dipolar interactions is examined. New Monte Carlo simulation results are presented for the dipolar Yukawa hard sphere (DYHS) fluid with very small values of the attractive Yukawa well depth, almost two orders of magnitude smaller than the characteristic dipolar interaction energy. In this way, it is possible to approach the dipolar hard sphere (DHS) limit. It is found that phase separation is not observable beyond a critical value of the Yukawa energy parameter, even though in thermodynamic and structural terms, the DYHS and DHS systems are very similar. It is suggested that either some very subtle physics distinguishes the DYHS and DHS systems, or the observation of a phase transition in DHSs is precluded by finite-size effects.},
	keywords = {BEHAVIOR, COEXISTENCE, dipolar hard spheres, FERROFLUIDS, FLUIDS, HARD-SPHERES, Monte Carlo simulation, MONTE-CARLO, ORDER, SIMULATION, SYSTEM, THERMODYNAMICS, vapour-liquid transition},
	isbn = {0026-8976},
	url = {<Go to ISI>://000266244700014},
	author = {Ganzenmuller, G. and Patey, G. N. and Camp, P. J.}
}
@article {1513,
	title = {The interaction of patterned solutes in binary solvent mixtures},
	journal = {Journal of Chemical Physics},
	volume = {124},
	number = {9},
	year = {2006},
	note = {ISI Document Delivery No.: 019IHTimes Cited: 1Cited Reference Count: 44},
	month = {Mar},
	pages = {11},
	type = {Article},
	abstract = {Mean solute-solute forces and solute-induced solvent structure are investigated for pairs of chemically patterned (patched) solutes in binary mixtures near demixing coexistence. The isotropic and anisotropic hypernetted-chain integral equation theories as well as a superposition approximation are solved and compared. The patched solutes consist of one end that favors the majority species in the mixture while the other end favors the minority species. A wide range of patch sizes is considered. The isotropic and anisotropic theories are found to be in good agreement for most orientations, including the most attractive and most repulsive configurations. However, some differences arise for asymmetrical orientations where unlike ends of the solute particles face each other. In contrast, superposition often gives a rather poor approximation to the mean force, even though the results obtained for the solvent densities agree qualitatively with the anisotropic theory. The mean force is sensitive to small differences in the densities particularly near demixing. For patched solutes the influence of demixinglike behavior is evident both in the orientational dependence and in the range of the mean force acting between solutes. (c) 2006 American Institute of Physics.},
	keywords = {BRIDGE DIAGRAM SERIES, FLUID, HARD-SPHERES, HYDROPHOBIC SURFACES, LENNARD-JONES, LIQUID MIXTURES, MACROPARTICLES, PHASE-TRANSITION, RANGE, SPHERICALLY INHOMOGENEOUS FLUIDS, WATER},
	isbn = {0021-9606},
	url = {<Go to ISI>://000235828300034},
	author = {Overduin, S. D. and Patey, G. N.}
}
@article {446,
	title = {Orientational ordering and disordering of a simple dipolar fluid under shear flow},
	journal = {Journal of Chemical Physics},
	volume = {117},
	number = {19},
	year = {2002},
	note = {ISI Document Delivery No.: 609YVTimes Cited: 4Cited Reference Count: 68},
	month = {Nov},
	pages = {9016-9027},
	type = {Article},
	abstract = {Nonequilibrium molecular dynamics simulations are performed for a simple dipolar fluid under planar Couette flow. Under this shear flow, the fluid{\textquoteright}s spatial structure becomes distorted, and the pair distribution function is anisotropic. At low shear rates, the dipoles respond to this distortion by orientationally ordering along an axis where the fluid structure is most compressed, giving a shear-induced ferroelectric fluid state. At high shear rates above a critical value, the orientational order decreases. We argue that this disordering can be attributed to the onset of large fluctuations in the director{\textquoteright}s orientation about the compression axis at the critical shear rate. We also observe the director can "hop" between "up" and "down" directions along the compression axis. These hops are fast and infrequent events. (C) 2002 American Institute of Physics.},
	keywords = {BOUNDARY-CONDITIONS, COMPUTER-SIMULATION, DENSITY-FUNCTIONAL THEORY, HARD-SPHERES, LIQUID-CRYSTAL, LIVING POLYMERS, MODEL, NONEQUILIBRIUM-MOLECULAR-DYNAMICS, PHASE-SEPARATION, POLAR CLUSTERS, SELF-DIFFUSION},
	isbn = {0021-9606},
	url = {<Go to ISI>://000178934700045},
	author = {McWhirter, J. L. and Patey, G. N.}
}
@article {5104,
	title = {Ferroelectric order in positionally frozen dipolar systems},
	journal = {Journal of Chemical Physics},
	volume = {115},
	number = {10},
	year = {2001},
	note = {ISI Document Delivery No.: 466LTTimes Cited: 13Cited Reference Count: 46},
	month = {Sep},
	pages = {4718-4731},
	type = {Article},
	abstract = {We discuss the possibility of long-range ferroelectric order in an amorphous dipolar system. Our model consists of spheres with frozen positions and freely rotating three-dimensional dipole moments. Correlation functions are calculated by means of the hypernetted-chain integral theory combined with the replica method. Our results suggest that inhomogeneities in the frozen spatial structure induce a gradual local freezing of the dipole axes upon decreasing temperature. However, at sufficiently high densities and dipole moments, the long-range interactions dominate the short-range frustration, resulting in a ferroelectric transition. The estimated transition temperatures depend strongly on the degree of spatial correlation in the underlying system of frozen spheres. For a randomly frozen system, we find that the transition temperature is considerably lower than that predicted by mean field theory, and also lower than the temperature where simulations indicate the onset of glass-like behavior. Strong positional correlations can push the transition toward temperatures higher even than those observed for dipolar fluids. (C) 2001 American Institute of Physics.},
	keywords = {GROUND-STATE, HARD-SPHERES, HYPERNETTED-CHAIN APPROXIMATION, INTEGRAL-EQUATION THEORY, ISING-MODEL, LIQUID-VAPOR INTERFACE, LOCAL-MEAN-FIELD, orientational order, ORNSTEIN-ZERNIKE APPROXIMATION, RANDOM ANISOTROPY},
	isbn = {0021-9606},
	url = {<Go to ISI>://000170647600035},
	author = {Klapp, S. H. L. and Patey, G. N.}
}
@article {4848,
	title = {Crystallization of dipolar spheres: A discussion of second-order density functional theory},
	journal = {Journal of Chemical Physics},
	volume = {112},
	number = {24},
	year = {2000},
	note = {ISI Document Delivery No.: 324HYTimes Cited: 6Cited Reference Count: 43},
	month = {Jun},
	pages = {10949-10956},
	type = {Article},
	abstract = {We investigate the application of second-order density functional theory to the crystallization of dipolar hard and soft spheres. It is shown that the results are highly sensitive to the repulsive part of the pair potential, and to the symmetry of the fluid phase considered in the density functional theory. In general, the theoretical results for dipolar soft spheres (with r(-12) repulsion) are found to be physically more reasonable than those obtained for dipolar hard spheres. In particular, the fluid-solid density gap is greatly reduced and lies in the range expected on physical grounds and from simulations. However, theories constructed by expanding about the isotropic fluid phase overestimate the stability of the ferroelectric solid for both models, and fail to predict the stable ferroelectric fluids found in computer simulations. We have carried out calculations using ferroelectric dipolar fluids with both perfect and fluctuating orientational order as "starting points" in the density functional expansion. The results demonstrate the high sensitivity of the theory to the underlying fluid state, and strongly indicate the existence of stable ferroelectric fluids in accord with computer simulations. (C) 2000 American Institute of Physics. [S0021-9606(00)50924-6].},
	keywords = {FLUIDS, HARD-SPHERES, INTEGRAL-EQUATIONS, LIQUID-VAPOR INTERFACE, NEMATIC PHASE, orientational order, PHASE-TRANSITIONS, SOFT SPHERES, SOLID-PHASES, STABILITY},
	isbn = {0021-9606},
	url = {<Go to ISI>://000087617300033},
	author = {Klapp, S. H. L. and Patey, G. N.}
}
@article {4895,
	title = {Forces between like-charged walls in an electrolyte solution: A comparison of McMillan-Mayer results for several models},
	journal = {Journal of Chemical Physics},
	volume = {113},
	number = {7},
	year = {2000},
	note = {ISI Document Delivery No.: 344XYTimes Cited: 8Cited Reference Count: 28},
	month = {Aug},
	pages = {2851-2855},
	type = {Article},
	abstract = {The interaction of like-charged walls immersed in aqueous solutions with monovalent counterions is investigated at the McMillan-Mayer (MM) level of description. The net pressure acting between the walls is obtained by applying the anisotropic hypernetted-chain theory. The MM approach requires solvent-averaged ion-ion potentials of mean force as input. Results based on "realistic" models for Na+ and Cl- in water are available in the literature and these are used in the present calculations. The wall-wall interactions obtained can differ dramatically from the primitive model (dielectric continuum solvent) case. For some models attractive wall-wall forces are observed at small separations. The MM theory is found to be rather sensitive to details of the counterion-counterion potential of mean force, and different models for the same counterion can give qualitatively different results. At present it is difficult to evaluate the relative accuracy of the different models that have been proposed. However, the results presented here give at least an idea of the interesting possibilities that lie in the physically realistic range. (C) 2000 American Institute of Physics. [S0021-9606(00)50331-6].},
	keywords = {APPROXIMATION, DOUBLE-LAYER, FORCE, HARD-SPHERES, IMAGE INTERACTIONS, INHOMOGENEOUS COULOMB FLUIDS, MEAN, MOLECULAR-DYNAMICS, PLANAR SURFACES, SODIUM-CHLORIDE, WATER},
	isbn = {0021-9606},
	url = {<Go to ISI>://000088787400034},
	author = {Otto, F. and Patey, G. N.}
}
@article {4896,
	title = {Forces between like-charged walls in electrolyte solution: Molecular solvent effects at the McMillan-Mayer level},
	journal = {Journal of Chemical Physics},
	volume = {112},
	number = {20},
	year = {2000},
	note = {ISI Document Delivery No.: 310WCTimes Cited: 13Cited Reference Count: 36},
	month = {May},
	pages = {8939-8949},
	type = {Article},
	abstract = {The force between two like-charged walls immersed in electrolyte solution is obtained for models that include solvent effects at the McMillan-Mayer (MM) level. In these models the solvent is not represented by discrete particles but exerts its influence through solvent-averaged ion-ion potentials of mean force which serve as effective potentials. This simplification allows the numerical solution of accurate anisotropic integral equation theories, and the anisotropic hypernetted-chain (AHNC) approximation is used in the present calculations. It is shown that the MM results may differ significantly from those of the primitive model (PM) which treats the solvent as a dielectric continuum. Most interestingly, we find that at the MM level the force between like-charged walls at small separations and with realistic surface charges can be attractive for monovalent counterions. This attraction is due to solvent effects on the effective counterion-counterion interaction and not to the correlated charge fluctuations that give rise to the attractions found for divalent counterions in the PM case. The possible relevance of our observations in the interpretation of experimental force measurements is briefly discussed. (C) 2000 American Institute of Physics. [S0021-9606(00)51720-6].},
	keywords = {AQUEOUS-ELECTROLYTES, DOUBLE-LAYERS, electric, HARD-SPHERES, IMAGE, INFINITE DILUTION, INHOMOGENEOUS COULOMB FLUIDS, interactions, ION-ION CORRELATIONS, MICA SURFACES, MONTE-CARLO SIMULATIONS, PLANAR SURFACES},
	isbn = {0021-9606},
	url = {<Go to ISI>://000086851200025},
	author = {Otto, F. and Patey, G. N.}
}
@article {4496,
	title = {Orientational order in model dipolar fluids},
	journal = {Physical Review E},
	volume = {60},
	number = {4},
	year = {1999},
	note = {ISI Document Delivery No.: 250XETimes Cited: 10Cited Reference Count: 17Part B},
	month = {Oct},
	pages = {4280-4284},
	type = {Article},
	abstract = {Fluids of hard spheres each carrying two parallel point dipoles have been investigated using constant-volume Monte Carlo computer simulations. The results show that both ferroelectric and antiferroelectric fluid phases can be stabilized at high density and low temperature by dipolar interactions alone, if the separation between the dipoles on each sphere is sufficiently large. A simple lattice calculation provides some insight into the balance between dipole energy and orientational entropy which governs the polarization state. [S1063-651X(99)00610-8].},
	keywords = {HARD-SPHERES, MONTE-CARLO, PHASES, SIMULATION, SYSTEMS},
	isbn = {1063-651X},
	url = {<Go to ISI>://000083414900011},
	author = {Camp, P. J. and Patey, G. N.}
}
@article {4441,
	title = {Theory of ion solvation dynamics in mixed dipolar solvents},
	journal = {Journal of Chemical Physics},
	volume = {109},
	number = {8},
	year = {1998},
	note = {ISI Document Delivery No.: 114ZNTimes Cited: 38Cited Reference Count: 32},
	month = {Aug},
	pages = {3222-3231},
	type = {Article},
	abstract = {Time dependent density functional theory in its "extended linear" or "surrogate" form is used to investigate the dynamics of selective ion solvation in binary dipolar solvents. It is shown that simple analytical approximations that trap the basic physics of the solvation process can be obtained. In particular, it is found that the relaxation of:the solvent number densities about a charged solute is governed by two distinct modes clearly associated with electrostriction and redistribution processes. This is consistent with the physical picture suggested by molecular dynamics (MD) simulations. The solvent polarization relaxation is also dominated by two modes associated with the-two rotational diffusion constants of the binary solvent. In addition to the analytical approximations, full numerical solutions of the extended linear theory are obtained and the dependence of the relaxation on solvent density and solute charge is discussed. Detailed comparisons of the theory with MD simulations for a closely related model indicate that the theory is qualitatively correct, but quantitatively poor generally predicting relaxation rates which are too fast. This is due mainly to the neglect of inertial or non-Markovian effects in the theoretical approach. (C) 1998 American Institute of Physics. [S0021-9606(98)50132-8]},
	keywords = {COLLECTIVE ORIENTATIONAL RELAXATION, DIELECTRIC-RELAXATION, ELECTROLYTE-SOLUTIONS, HARD-SPHERES, INVARIANT EXPANSION, LIQUIDS, MEAN, MIXTURES, MOLECULAR THEORY, ORNSTEIN-ZERNIKE EQUATION, SPHERICAL MODEL},
	isbn = {0021-9606},
	url = {<Go to ISI>://000075639200032},
	author = {Yoshimori, A. and Day, T. J. F. and Patey, G. N.}
}
@article {3924,
	title = {An investigation of the influence of solute size and insertion conditions on solvation thermodynamics},
	journal = {Journal of Chemical Physics},
	volume = {106},
	number = {19},
	year = {1997},
	note = {ISI Document Delivery No.: WZ032Times Cited: 32Cited Reference Count: 52},
	month = {May},
	pages = {8165-8195},
	type = {Article},
	abstract = {In this paper we examine the influence of solute size and insertion conditions on solvent structural changes and excess thermodynamic properties in the infinite dilution limit. A general integral equation approach which can be applied under arbitrary conditions is given and isothermal-isochoric and isothermal-isobaric insertions are discussed in detail. Scaling relationships valid in the large solute limit are determined for both structural and thermodynamic properties. This is done by considering macroscopic thermodynamic relationships and explicit evaluation of low solvent density expansions of pair correlation functions. The hypernetted-chain and reference hypernetted-chain closure approximations are used to obtain numerical results for the insertion of hard sphere solutes of varying diameter into hard sphere, dipolar hard sphere and water-like solvents. The results obtained give a good deal of insight into the nature of solvation of inert solutes. It is shown that for all three solvents the excess properties are very well represented by a function obtained by summing terms proportional to the solute volume, surface area and diameter. One would expect such a result for large solutes, but here we show that this expression extrapolates all the way down to solutes comparable in size to the solvent particles. Further, it is shown that both the numerical value, and, more importantly, the physical interpretation of the excess thermodynamic properties strongly depend on the insertion conditions. Under all insertion conditions the chemical potential is a local property in the sense that it is completely determined by solute-solvent correlations which are important only in the immediate vicinity of the solute. However, this is not true of the excess energy, enthalpy and entropy which all contain nonlocal contributions arising essentially from changes in the actual or effective solvent density depending on the insertion conditions. We demonstrate that the nonlocal contributions can be very significant and therefore the excess energies, enthalpies and entropies often cannot provide useful information about solvent structure near solutes. This has significant implications for models which attempt to rationalize excess thermodynamics in terms of local solvent structure in the vicinity of solute particles. (C) 1997 American Institute of Physics.},
	keywords = {COMPUTER-SIMULATION, ELECTROLYTE-SOLUTIONS, FREE-ENERGIES, HARD-SPHERES, HYDROPHOBIC HYDRATION, HYPERNETTED-CHAIN APPROXIMATION, INVARIANT EXPANSION, MEAN, ORNSTEIN-ZERNIKE EQUATION, SPHERICAL MODEL, TEMPERATURE-DEPENDENCE},
	isbn = {0021-9606},
	url = {<Go to ISI>://A1997WZ03200027},
	author = {Cann, N. M. and Patey, G. N.}
}
@article {2921,
	title = {MOLECULAR-SOLVENT MODEL FOR AN ELECTRICAL DOUBLE-LAYER - ASYMMETRIC SOLVENT EFFECTS},
	journal = {Journal of Physical Chemistry},
	volume = {97},
	number = {49},
	year = {1993},
	note = {ISI Document Delivery No.: ML667Times Cited: 25Cited Reference Count: 36},
	month = {Dec},
	pages = {12909-12918},
	type = {Article},
	abstract = {Previous reference hypernetted-chain theoretical results for electrical double layers using a multipolar solvent with tetrahedral geometry are extended here to a more accurate water model having only C2v symmetry. This model exhibits a net polarization at a flat uncharged surface with the positive end of the dipoles inclined into the fluid; the resulting surface potential is compared with both computer simulation and experimental results for the free surface of liquid water. This model also responds differently to positively and negatively charged surfaces, both with and without electrolyte. This leads to an asymmetry in the differential capacitance of the electrical double layer.},
	keywords = {APPROXIMATION, AQUEOUS-ELECTROLYTE SOLUTIONS, CHARGED SURFACES, HARD-SPHERES, LIQUID VAPOR INTERFACE, MIXTURES, ORIENTATIONAL STRUCTURE, PROPERTIES, SIMULATION, THERMODYNAMIC, WATER},
	isbn = {0022-3654},
	url = {<Go to ISI>://A1993ML66700045},
	author = {Torrie, G. M. and Patey, G. N.}
}
@article {2930,
	title = {ORIENTATIONAL ORDER IN SIMPLE DIPOLAR FLUIDS - DENSITY-FUNCTIONAL THEORY AND ABSOLUTE-STABILITY CONDITIONS},
	journal = {Physical Review E},
	volume = {47},
	number = {1},
	year = {1993},
	note = {ISI Document Delivery No.: KY134Times Cited: 59Cited Reference Count: 29},
	month = {Jan},
	pages = {506-512},
	type = {Article},
	abstract = {The formation of ferroelectric liquid crystals by simple dipolar models is investigated using density-functional theory and absolute-stability analysis. It is emphasized that for such systems well defined results can only be found by specifying exactly how the long-range dipolar interactions are treated. Explicit formal expressions are derived for mean-reaction-field boundary conditions and these are combined with integral-equation approximations in order to obtain numerical results for fluids of dipolar hard and soft spheres. The calculations predict isotropic-to-ferroelectric-nematic transitions in qualitative agreement with computer simulations. The quantitative agreement, however, is rather poor.},
	keywords = {COMPUTER-SIMULATION, ELECTROSTATIC SYSTEMS, equation, HARD-SPHERES, INVARIANT EXPANSION, MEAN SPHERICAL MODEL, ORNSTEIN-ZERNIKE, PERIODIC BOUNDARY-CONDITIONS, POLAR SYSTEMS, TRANSITION},
	isbn = {1063-651X},
	url = {<Go to ISI>://A1993KY13400062},
	author = {Wei, D. Q. and Patey, G. N. and Perera, A.}
}
