Fluid-solid transition

Figure 3. (a) Two-dimensional, bond orientational order parameter average values in the molecular fluid layers of LI ecu confined in a multi-walled carbon nanotube of diameter D=9norder parameter values for the contact, second, third and fourth layers, respectively. The dotted line represents the bulk solid-fluid transition temperature, (b) Positional and orientational pair correlation functions in the unwraiqred contact layer of U CCU confined in a multi-walled carbon nanotube of diameter D=9.1< (5 nm) showing liquid phase at 7=262 K and crystal phase at 7=252 K. 

The solid-fluid transition in the hard-sphere system has been the subject of great interest for about 50 years now. Although it was originally only a computer model, researchers in colloid science have come close to a complete experimental realization of the hard-sphere model [2,3]. The hard-sphere system is one with an intermolecular potential of the form... 

This is not to say that the theoretical work on the problem of SFE has not been important. The search for theoretical methods for predicting the solid-fluid transition ranging from the early work of Kirkwood to the most recent studies with DFT have made an important contribution to our understanding, as well as serving as a stimulus to other efforts in experiment and computer simulation. Moreover, our general understanding of the statistical mechanics of condensed phase systems has benefited considerably from this work. On... 

SaUcar, R.A., Hassan, P.A., Samant, S.D., Valaulikar, B.S., Kumar, V.V., Kem, F., Candu, S.J., Manohar, C. A thermally reversible vesicle to micelle transition driven by a surface solid-fluid transition. 7. Chem. Soc. Chem. Commun. 1996,1223-1224. 

The CS pressures are close to the machine calculations in the fluid phase, and are bracketed by the pressures from the virial and compressibility equations using the PY approximation. Computer simulations show a fluid-solid phase transition tiiat is not reproduced by any of these equations of state. The theory has been extended to mixtures of hard spheres with additive diameters by Lebowitz [35], Lebowitz and Rowlinson [35], and Baxter [36]. 

Reiss H and Hammerich ADS 1986 Hard spheres scaled particle theory and exact relations on the existence and structure of the fluid/solid phase transition J. Phys. Chem. 90 6252... 

Runge, K. J. Chester, G. V., Solid-fluid phase transition of quantum hard spheres at finite temperature, Phys. Rev. B 1988, 38, 135-162... 

A transition from fluid to solid in the mechanical response accompanying the frustrated fluid-solid phase transition,... 

Figure 10 The average width of the NMR spectrum (Mi) as a function of temperature and pH. Closed circles pH 5.2 open circles pH 6.2 closed triangles pH 7.4. Repetition time 50 sec at all temperatures where the sample contained some solid component, then 1 sec at higher temperatures. (In practice, the quadrupolar echo intensity was checked every few degrees at the 1-sec repetition time toward the completion of the solid-to-fluid transition, and when the echo intensity differed by < 1% between the short and long repetition times, a l-sec repetition time was used for all higher temperatures.)...

The lamellar gel-lamellar liquid-crystalline (L - L ) phase transition, frequently also referred to as (chain-)melting, order-disorder, solid-fluid, or main transition, is the major energetic event in the lipid bilayers and takes place with a large enthalpy change. It is associated with rotameric disordering of the hydrocarbon chains, increased headgroup hydration, and increased... 

P. Adams and J. R. Henderson, Molecular Dynamics Simulations of Wetting and Drying in U Models of Solid-Fluid Interfaces in the Presence of Liquid-Vapor Coexistence, Mol. Phys. 73 (1991) 1383-1399 S. Sokolowski and J. Fischer, Wetting Transitions at the Ar-C02 Interface Molecular Dynamics Studies, Phys. Rev. A 41 (1990) 6866-6870 S. Dhawan, M. E. Reimel, L. E. Scriven and H. T. Davis, Wetting transitions at a Solid-Fluid Interface, J. Chem. Phys. 94 (1991), 4479-4489. 

The MD simulations showed liquid-solid phase transitions, at a constant temperature, with the variation in the equilibrium vapor-phase pressure below saturated one, and prove the importance of the tensile effect on freezing in nanopores. The capillary effect on shift in freezing point was successfully described by a model based on the concept of pressure felt by the pore fluid. 

As a typical example of CEDFT calculations, we present in Fig. 1 the capillary condensation isotherm of N2 in a cylindrical pore mimicking the pore channel in MCM-41 mesoporous molecular sieves. The isotherm is presented in co-ordinates adsorption N versus chemical potential p Calculations were performed at 77 K for the internal diameter of 3.3 nm up to the saturation conditions, point H. We used Tarazona s representation of the Helmholtz free energy [6] with the parameters for fluid-fluid and solid-fluid interaction potentials, which were employed in our previous papers [7]. We distinguish three regions on the isotherm. The adsorption branch OC corresponds to consecutive formation of adsorption layers. Note that the sharp transitions between the consecutive layers are not observed in experiments. They are caused by a well-known shortcoming of the model employed, which ignores intrinsic to real... 

It is still uncertain whether or not the solid-hquid equihbrium Hne terminates at a critical point. Munster has recently given theoretical reasons for behoving that all first-order transitions possess a critical point, but this conclusion is contrary to that reached by Domb, j"j whose theory predicts the absence of a solid-fluid critical point. The experimental work of Simon and his co-workers on the melting line of hehum shows no evidence for a critical point up to a pressure of 9,000 atm. and a temperature of 56° K. Alder and Jura have, however, made calculations which suggest that a soHd-fluid critical point should... 

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