Surface tension of normal and branched alkanes

We present results illustrating the effects of using explicit summation terms for the r − 6 dispersion term on the interfacial properties of normal and branched alkanes. We study two all-atom force fields, the OPLS force field of Jorgensen et al. and the exponential-6 force field of Smith and co-workers. We find that the OPLS force field offers excellent agreement with experimental data for surface tension at low temperatures, while the Smith force field agrees well at lower molecular weights. Cutting off the dispersion term at a finite distance r c can have pronounced effects on interfacial properties, with as much as a 20% reduction in the measured liquid–vapour surface tension for r c = 12 Å. Our results also suggest the need for long simulation for normal alkanes, as equilibrium values are not reached for nearly 3 ns or more. Examining the effect of molecular weight on the surface tension, we find that the data for both force fields show excellent agreement with the dependence proposed in the literature.

[1]  P. Cummings,et al.  Molecular simulations of liquid-liquid interfacial properties: water-n-alkane and water-methanol-n-alkane systems. , 2003, Physical review. E, Statistical, nonlinear, and soft matter physics.

[2]  T. Darden,et al.  The effect of long‐range electrostatic interactions in simulations of macromolecular crystals: A comparison of the Ewald and truncated list methods , 1993 .

[3]  Alfred Leipertz,et al.  Viscosity and Surface Tension of Saturated n-Pentane , 2004 .

[4]  B. Smit,et al.  Molecular dynamics simulations of the surface tension of n-hexane, n-decane and n-hexadecane , 2002 .

[5]  T. Darden,et al.  Liquid–vapour equilibrium of n -alkanes using interface simulations , 2006 .

[6]  G. Gaines,et al.  The molecular weight dependence of polymer surface tension , 1969 .

[7]  G. Saville,et al.  Computer simulation of a gas–liquid surface. Part 1 , 1977 .

[8]  Oleg Borodin,et al.  Development of many-body polarizable force fields for Li-battery components: 1. Ether, alkane, and carbonate-based solvents. , 2006, The journal of physical chemistry. B.

[9]  B. Ocko,et al.  Surface freezing of chain molecules at the liquid-liquid and liquid-air interfaces. , 2005, Faraday discussions.

[10]  D. Y. Yoon,et al.  Static and Dynamic Properties of a n-C100H202 Melt from Molecular Dynamics Simulations , 1997 .

[11]  D. Patterson,et al.  The Prediction of Surface Tensions of Liquid Polymers , 1971 .

[12]  Capillary waves at the liquid-vapor interface and the surface tension of water. , 2006, The Journal of chemical physics.

[13]  G. Gaines,et al.  Surface tension of homologous series of liquids , 1973 .

[14]  Bertrand Guillot,et al.  A reappraisal of what we have learnt during three decades of computer simulations on water , 2002 .

[15]  K. Mecke,et al.  X-ray synchrotron study of liquid-vapor interfaces at short length scales: effect of long-range forces and bending energies. , 2003, Physical review letters.

[16]  Gary S Grest,et al.  Application of Ewald summations to long-range dispersion forces. , 2007, The Journal of chemical physics.

[17]  Daniel Duque,et al.  Interfacial properties of Lennard-Jones chains by direct simulation and density gradient theory. , 2004, The Journal of chemical physics.

[18]  Maeda,et al.  Surface supercooling and stability of n-alkane films , 2000, Physical review letters.

[19]  J. Banavar,et al.  Computer Simulation of Liquids , 1988 .

[20]  Bo Shi,et al.  Molecular dynamics simulation of the density and surface tension of water by particle-particle particle-mesh method. , 2006, The Journal of chemical physics.

[21]  I. Marrucho,et al.  Surface Tension of Decane Binary and Ternary Mixtures with Eicosane, Docosane, and Tetracosane , 2005 .

[22]  Jim Glosli,et al.  Comments on P3M, FMM, and the Ewald method for large periodic Coulombic systems , 1996 .

[23]  Michael L. Klein,et al.  A coarse grain model for n-alkanes parameterized from surface tension data , 2003 .

[24]  Capillary-Wave and Chain-Length Effects at Polymer/Polymer Interfaces , 1997, cond-mat/9709196.

[25]  J. Singh,et al.  Calculation of phase coexistence properties and surface tensions of n-alkanes with grand-canonical transition-matrix monte carlo simulation and finite-size scaling. , 2006, The journal of physical chemistry. B.

[26]  Steve Plimpton,et al.  Fast parallel algorithms for short-range molecular dynamics , 1993 .

[27]  J. Kirkwood,et al.  The Statistical Mechanical Theory of Surface Tension , 1949 .

[28]  Dick Bedeaux,et al.  Tail corrections to the surface tension of a Lennard-Jones liquid-vapour interface , 1995 .

[29]  N. Karasawa,et al.  Acceleration of convergence for lattice sums , 1989 .

[30]  I. Marrucho,et al.  Surface Tension of Heptane, Decane, Hexadecane, Eicosane, and Some of Their Binary Mixtures , 2002 .

[31]  A. F. Bakker,et al.  A molecular dynamics simulation of the Lennard‐Jones liquid–vapor interface , 1988 .

[32]  D. E. Williams,et al.  Accelerated convergence of crystal-lattice potential sums , 1971 .

[33]  H. G. Petersen,et al.  An algorithm for the simulation of condensed matter which grows as the 3/2 power of the number of particles , 1988 .

[34]  E. Lightfoot,et al.  The dynamics of thin liquid films in the presence of surface‐tension gradients , 1971 .

[35]  W. L. Jorgensen,et al.  Development and Testing of the OPLS All-Atom Force Field on Conformational Energetics and Properties of Organic Liquids , 1996 .

[36]  Oleg Borodin,et al.  A revised quantum chemistry‐based potential for poly(ethylene oxide) and its oligomers in aqueous solution , 2002, J. Comput. Chem..

[37]  H. Berendsen,et al.  COMPUTER-SIMULATION OF MOLECULAR-DYNAMICS - METHODOLOGY, APPLICATIONS, AND PERSPECTIVES IN CHEMISTRY , 1990 .

[38]  E. Kerr,et al.  The Orthobaric Surface Tensions and Thermodynamic Properties of the Liquid Surfaces of the n—Alkanes, C5 to C28 , 1953 .

[39]  Bernard R Brooks,et al.  Isotropic periodic sum: a method for the calculation of long-range interactions. , 2005, The Journal of chemical physics.

[40]  Faraday Discuss , 1985 .

[41]  J. Ilja Siepmann,et al.  Novel Configurational-Bias Monte Carlo Method for Branched Molecules. Transferable Potentials for Phase Equilibria. 2. United-Atom Description of Branched Alkanes , 1999 .