Enhanced septahedral ordering in cold Lennard-Jones fluids.

نویسندگان

  • Paul C Whitford
  • George D J Phillies
چکیده

We report molecular dynamics calculations on a two-component, cold, 15,625 particle, three-dimensional Lennard-Jones fluid. We calculated spherical harmonic components Q(LM) for the density of particles in the first coordination shell of each particle, as well as their spherical invariants , time-correlation functions, and wavelet density decompositions. The spherical invariants show that noncrystalline septahedral () ordering is important, especially at low temperature. While < Q210> could arise from icosahedral ordering, its behavior so closely tracks that of the nonicosahedral that alternative origins for need to be considered. Time correlation functions of spherical harmonic components are bimodal, with a faster temperature-independent mode and a slow, strongly temperature-dependent mode. Volume wavelet decompositions show that when T is reduced, the correlation length of increases, especially below T=0.7 , but that the correlation length of is independent of T .

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Lennard-Jones Energy Parameter for Pure Fluids from Scaled Particle Theory

By considering the fact that the surface tension of a real fluid arises from a combination of both repulsive and attractive forces between molecules, a new expression for the interfacial tension has been derived from scaled particle theory (SPT)  based on the work of cavity formation and the interaction energy between molecules. At the critical temperature, the interfacial tension between c...

متن کامل

THE DENSITY PROFILES OF A LENNARD -JONES FLUID CONFINED TO A SLIT

The structure of fluids confined by planar walls is studied using density functional theory. The density functional used is a generalized form of the hypernetted chain (HNC) functional which contains a term third order in the density. This term is chosen to ensure that the modified density functional gives the correct bulk pressure. The proposed density functional applied to a Lennard-Jones...

متن کامل

The Modified Lennard-Jones and Devonshire Equation of State

Lennard-Jones-Devonshire equation of state is an old but theoretical based EOS. The concept of the nearest neighboring molecules or coordination number is proposed to be a function of temperature and volume, whereas it is a constant in the original. The dilute gas and hard sphere limits of molecules are employed to determine this function. Improvement of this modification is demonstrated by pro...

متن کامل

Nonequilibrium anisotropic phases, nucleation, and critical behavior in a driven Lennard-Jones fluid

We describe short-time kinetic and steady-state properties of the nonequilibrium phases, namely, solid, liquid, and gas anisotropic phases in a driven Lennard-Jones fluid. This is a computationally convenient two-dimensional model which exhibits a net current and striped structures at low temperature, thus resembling many situations in nature. We here focus on both critical behavior and details...

متن کامل

Phase diagrams of Lennard-Jones fluids

Smit and Frenkel’ have shown that the phase diagram of the two-dimensional Lennard-Jones fluid depends largely on the details of the truncation of the potential. In this Note, Gibbs-ensemble calculations are reported for the three-dimensional Lennard-Jones fluid. As expected, the phase diagram for this system also depends significantly on the details of the truncation. The Lennard-Jones potenti...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Physical review. E, Statistical, nonlinear, and soft matter physics

دوره 72 2 Pt 1  شماره 

صفحات  -

تاریخ انتشار 2005