Reorienatational dynamics of cholesterol molecules in thin film surrounded carbon nanotube: Molecular dynamics simulations

doi:10.1016/j.molstruc.2006.01.064

Journal of Molecular Structure

Volumes 792–793, 3 July 2006, Pages 216-220

https://doi.org/10.1016/j.molstruc.2006.01.064 Get rights and content

Abstract

We have made simulations of the system composed of single walled carbon nanotube (SWNT) surrounded by n=9, 13, 17 cholesterol (C₂₇H₄₆O) molecules. The mean square displacement, radial distribution function, diffusion coefficient, rotational and translational velocity correlations functions have been calculated for several temperatures. The qualitative interpretation of dynamics of cholesterol molecule in such specific environment is presented.

Introduction

The discovery of carbon nanotubes [1] has initiated a number of scientific investigations devoted to the study of their electrical, mechanical, optical, chemical and thermal properties [2], [3], [4], [5], [6], [7], [8]. Recently, however, there has been increasing activity in investigating small, finite-size SWNT-based mixture systems, because they are expected to exhibit interesting properties for nanotechnological applications [9], [10]. The experimental studies of these systems still encounter natural difficulties, that is why the computer simulation methods becoming valuable tools for exploratory research on these systems. In this paper, we present the computer simulation study (MD) [11] of a nanosize cluster composed of the single walled carbon nanotube (SWNT) surrounded by cholesterol (chol) molecules. Needles to say, that cholesterol plays an important role in mammals, especially humans body [12].

Section snippets

Simulation details

As a typical representative of the family of carbon nanotubes, the armchair (10, 10) nanotube [9] was chosen. The Lennard–Jones (L–J) interaction potential V between the carbon atoms of the nanotube and the sites (atoms) of the cholesterol molecule (Fig. 1) as well as between cholesterol sites was applied.

The L–J potential energy is given by the formula $V (r_{i j}) = 4 ε [{(\frac{σ}{r_{i j}})}^{12} - {(\frac{σ}{r_{i j}})}^{6}]$ where ε is the minimum of the potential at a distance of 2^1/6σ, k_B is the Boltzmann constant and r_ij is the distance

Results

MD simulations for three concentrations of SWNT-cholesterol mixture cluster SWNT(chol)₉, SWNT(chol)₁₃ and SWNT(chol)₁₇ are presented. We made the simulations for several temperatures, beginning from the solid phase at T=250 K and ending at hot liquid phase around T=650 K, since the cluster vaporised at higher temperatures.

The calculated translational velocity autocorrelation function $C_{\vec{v}} (t) = 〈 \vec{v} (t) \vec{v} (0) 〉 \cdot {〈 \vec{v} (0) \vec{v} (0) 〉}^{- 1}$ of (C₂₇H₄₆O), where $\vec{v} (t)$ is the translational velocity of cholesterol

Acknowledgement

This work was supported in part by Ministry of Education and Science, Grant No. 0047/H03/2006/30.

References (20)

P. Raczyński et al.
J. Mol. Struct.
(2005)
M. Skrzypek et al.
J. Mol. Struct.
(2004)
S. Ijima
Nature
(1991)
T. Odom
Nature
(1998)
M.J. O'Connel
Science
(2002)
S. Fan
Science
(1999)
J. Kong
Science
(2000)
M.F. Islam
Phys. Rev. Lett.
(2004)
A. Dawid et al.
Phys. Rev. A
(1998)
A. Dawid et al.
Phys. Rev. A
(1997)

There are more references available in the full text version of this article.

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Reorienatational dynamics of cholesterol molecules in thin film surrounded carbon nanotube: Molecular dynamics simulations

Abstract

Introduction

Section snippets

Simulation details

Results

Acknowledgement

J. Mol. Struct.

J. Mol. Struct.

Nature

Nature

Science

Science

Science

Phys. Rev. Lett.

Phys. Rev. A

Phys. Rev. A