A model equation of state of liquid C₆₀and thermodynamic properties along the liquid–vapour coexistence curve

Abstract

We present a model equation of state for C 60 based on a variational series mean spherical approximation for a double Yukawa fluid. This allows us to investigate the liquid-vapour coexistence curve and calculate the thermodynamic properties of liquid C 60 . The comparisons with computer simulation results, based on the Girifalco potential, suggest the importance of treating the attractive tail of the potential accurately. The estimated critical parameters, T c = 1943 K, ρ c = 0.477 nm −3 and P c = 34.2 bar, are in good agreement with Gibbs ensemble Monte Carlo simulation predictions. The results are discussed, making reference to previous studies.

Experimental and Molecular Modeling Study of Bubble Points of Hydrocarbon Mixtures in Nanoporous Media

“…The critical temperature of bulk decane was calculated to be 705 K compared to the true critical temperature of 618 K of bulk decane. The difference from the true critical temperature is attributed to the finite size effect described earlier and is also observed by researchers previously. − A suppression of 125 K in the critical temperature was calculated for confined decane, which is close to the observations made by other researchers. , The difference between the two values (bulk and confined) is more relevant than the actual values.…”

“…The pore wall–fluid interaction was captured using the Steele potential discussed above. The density plots were extrapolated from the near-critical region to estimate the critical temperature of pure decane in bulk and confined states. , As the system approaches a critical point, simulations performed on a finite system cannot capture the divergence of the correlation length that characterizes critical points, which may lead to abnormal values of critical properties (finite size effect − ). Hence, the critical density and critical temperature were calculated by extrapolation from the far-critical region in this paper.…”

New equation of state for double Yukawa potential with application to Lennard–Jones fluids

“…Quite recently, we applied the present EOS to investigate the thermodynamic properties of C 60 [28] by fitting the DY potential to the Garifalco potential [40]. The Physics and Chemistry of Liquids 247 performance of the present EOS was remarkably good -comparable to the computer simulation and to the other theoretical models.…”

“…Several authors [23][24][25][26][27][28] have shown that the DY potential, with suitably chosen parameters, provides accurate thermodynamic properties for simple liquids. The function form of DY potential with four fitting parameters 0 , E, 1 and 2 reads,…”

EXP6 fluids at extreme conditions modeled by two-Yukawa potentials

“…15,16 A drawback of existing theoretical methods for fluids which also sets limits to their applications is that they all are based on the assumption of the presence of very steep repulsive interactions between molecules at short separations. 32,33 Furthermore, the use of the Y reference may considerably improve accuracy of the perturbation methods: the more features captured by the reference, the less important become perturbation correction terms and, consequently, all considerations can ultimately be confined to a first-order expansion or further even to an augmented van der Waals ͑the simplified first-order expansion͒ theory only. Following recent developments in the field [17][18][19] which emphasize that it is not the character of interaction ͑i.e., for instance, repulsive interaction͒ but its range which determines the properties of fluid systems, we have recently developed an alternative to the HS-based method.…”