Phase coexistence properties

Panagiotopoulos A Z 1987. Direct Determination of Phase Coexistence Properties of Fluids by Mon Carlo Simulation in a New Ensemble. Molecular Physics 61 813-826. 

Kiyohara K, Gubbins KE, Panagiotopoulos AZ (1998) Phase coexistence properties of polarizable water models. Mol Phys 94(5) 803-808... 

Panagiotopoulos, A. Z., Direct determination of phase coexistence properties of fluids by Monte Carlo simulation in a new ensemble, Mol. Phys. 1987, 61, 813-826... 

In summary, the Gibbs ensemble MC methodology provides a direct and efficient route to the phase coexistence properties of fluids, for calculations of moderate accuracy. The method has become a standard tool for the simulation community, as evidenced by the large number of applications using the method. Histogram reweighting techniques (Chap. 3) have the potential for higher accuracy, especially if... 

Transferability to different temperatures is a particularly difficult task for polarizable water models. This statement is illustrated by the problems in predicting the PVT and phase coexistence properties. There are a handful of polarizable water models— including both dipole- and EE-based models— that are reasonably successful in predicting some of the structural and energetic changes in liquid water over a range of several hundred degrees. 

Phase Coexistence Properties of Polarizable Water Models. 

In Table I we show a comparison of phase coexistence properties for the hard sphere solid calculated from various theories. The three most accurate density functional theories are shown together with two sets of predictions based on cell theory. The first cell theory prediction shown is from Barker s... 

Martin M G and J I Siepmann 1999. Novel Configurational-bias Monte Carlo Method tor Branched Molecules Transferable Potentials for Phase Equilibria. 2 United-atom Description of Branched Alkanes Journal of Physical Chemistry 103 4508-4517 Metropolis N, A W Rosenbluth, M N Rosenbluth, A H Teller and E Teller 1953 Equation of State Calculations by Fast Computing Machines. Journal of Chemical Physics 21 1087-1092 Okamoto Y and U H E Hansmann 1995. Thermodynamics of HeUx-coU Transitions Studied by Multicanomcal Algorithms. Journal of Physical Chemistry 99 11276-11287 Panagiotopoulos A Z 1987. Direct Determination of Phase Coexistence Properties of Fluids by Monte Carlo Simulation in a New Ensemble. Molecular Physics 61.813-826 Pangali C, M Rao and B J Berne 1978 On a Novel Monte Carlo Scheme for Simulating Water and Aqueous Solutions Chemical Physics Letters 55 413-417. 

Smith WR, Triska B (1994) The reaction ensemble method for the computer simulation of chemical and phase equilibria I. Theory and basic examples. J Chem Phys 100 3019-3027 Kiyohara K, Spyriouni T, Gubbins KE et al (1996) Thermodynamic scaling Gibbs ensemble Monte Carlo a new method for determination of phase coexistence properties of fluids. Mol Phys 89 965-974... 

Potoff JJ, Panagiotopoulos AZ (2000) Surface tension of the three-dimensional Lennard-Jones fluid from hislogram-reweighting Monte Carlo simulations. J Chem Phys 112 6411-6416 Singh JK, Errington JR (2006) Calculation of phase coexistence properties and surface tensions of n-alkanes with grand-canonical transition-matrix Monte Carlo simulation and flnite-size scaling. J Phys Chem B 110 1369-1376... 

The recently proposed Exp-6 water model uses a more realistic exponential functional form for the repulsive interaction in Equation (12), and was specifically parameterized to reproduce the vapor-liquid phase coexistence properties (Errington and Panagiotopoulos 1998). However, it does not do as well as the TIP4P, SPC, and SPC/E models for the structure of liquid water, especially in terms of the oxygen-oxygen pair correlation function (Panagiotopoulos 2000). 

Simulations with an explicit interface appear, at first glance, to be relatively simple to implement and perform. Unlike most other methods discussed here, interfacial simulations can also be performed using molecular dynamics codes. However, they provide an inefficient route to the phase coexistence properties. Unless the properties of the interface itself (or the surface tension) are of interest, other methods discussed in the present chapter provide better alternatives. 

MD simulations were performed on an antiferromagnetic structure of ice Ih. This structure has a net dipole moment of zero. Haymet and Karim were able to obtain stable ice ih at a reasonable temperature and pressure and hence a stable ice-water interface under physical conditions reasonably close to experiment. (It should be noted that the precise phase coexistence properties of the TIP4P model are not known.) The diffusion constant and density profiles for the oxygen atoms across the interface were shown in Section 2 (Figures 2a and 2b, respectively). The bulk value of the diffusion constant was calculated from a separate simulation with density 1.02 g cm . The letters A-H in Figure 2(a) correspond to individual lattice plane layers through the interface and will be referred to in what follows. 

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