Disorder in the pseudohexagonal rotator phase of n-alkanes: molecular-dynamics calculations for tricosane

Molecular-dynamics calculations for a flexible-chain model have been used to study two, solid, bilayer phases of the n-alkane tricosane (C23H48). In the crystalline, orthorhombic phase at 311 K, the chains remain all-trans and fully ordered, with a herringbone packing. By contrast, in the pseudohexagonal (R I) rotator phase at about 320 K, a dramatic increase in longitudinal chain motion is observed, each chain has four well-defined orientations, and a significant number of conformational defects develop, with the latter occurring predominantly at the chain ends. The results of the simulations are in excellent agreement with experiment.

[1]  D. Frenkel,et al.  Thermodynamic stability of a smectic phase in a system of hard rods , 1988, Nature.

[2]  G. Pawley,et al.  Molecular dynamics studies of the condensed phases of n-butane and their transitions. I: Techniques and model results , 1987 .

[3]  Klein,et al.  Disorder at the bilayer interface in the pseudohexagonal rotator phase of solid n-alkanes. , 1987, Physical review letters.

[4]  J. Naghizadeh.  Quasi-two-dimensional phase transitions in paraffins , 2007 .

[5]  S. Yip,et al.  Molecular dynamics simulation of hydrocarbon molecules in condensed phases. I. Liquid n‐butane , 1986 .

[6]  Giovanni Ciccotti,et al.  Andersen's canonical-ensemble molecular dynamics for molecules with constraints , 1986 .

[7]  Michael L. Klein,et al.  Translational and rotational disorder in solid n‐alkanes: Constant temperature–constant pressure molecular dynamics calculations using infinitely long flexible chains , 1986 .

[8]  J. Clarke,et al.  Molecular dynamics computer simulation of polymer fiber microstructure , 1986 .

[9]  Michael L. Klein.  COMPUTER SIMULATION STUDIES OF SOLIDS , 1986 .

[10]  J. Ryckaert.  Special geometrical constraints in the molecular dynamics of chain molecules , 1985 .

[11]  Takashi Yamamoto.  Monte Carlo simulation of the crystal structure of the rotator phase of n‐paraffins , 1985 .

[12]  R. G. Snyder,et al.  The distribution of conformational disorder in the high‐temperature phases of the crystalline n‐alkanes , 1985 .

[13]  G. Ungar,et al.  Order in the rotator phase of n-alkanes , 1985 .

[14]  Mauro Ferrario,et al.  Constant pressure-constant temperature molecular dynamics for rigid and partially rigid molecular systems , 1985 .

[15]  G. G. Roberts,et al.  An applied science perspective of Langmuir-Blodgett films , 1985 .

[16]  D. Steele,et al.  An ab initio investigation of the torsional potential function of n-butane , 1985 .

[17]  J. Doucet,et al.  Rotational diffusion in the rotator phase of n‐alkanes , 1984 .

[18]  A. Craievich,et al.  Molecular motion and conformational defects in odd-numbered paraffins , 1984 .

[19]  A. Craievich,et al.  X‐ray study of the rotator phase of paraffins (IV): C27H56, C28H58, C29H60, C30H62, C32H66, and C34H70 , 1984 .

[20]  H. Mantsch,et al.  Infrared spectra of crystalline n-alkanes. Changes observed during the phase I → phase II transition , 1983 .

[21]  H. Casal,et al.  A 2H NMR study of the solid‐phase behavior of nonadecane , 1983 .

[22]  G. Ungar.  Structure of rotator phases in n-alkanes , 1983 .

[23]  R. G. Snyder,et al.  Nonplanar Conformers and the Phase Behavior of Solid n- Alkanes , 1982 .

[24]  R. G. Snyder,et al.  Interchain vibrational coupling in phase II (hexagonal) n‐alkanes , 1982 .

[25]  Herman J. C. Berendsen,et al.  MOLECULAR-DYNAMICS SIMULATION OF A BILAYER-MEMBRANE , 1982 .

[26]  A. Craievich,et al.  Evidence of a phase transition in the rotator phase of the odd‐numbered paraffins C23H48 and C25H52 , 1981 .

[27]  G. Zerbi,et al.  Molecular mechanics for phase transition and melting of n‐alkanes: A spectroscopic study of molecular mobility of solid n‐nonadecane , 1981 .

[28]  P J Flory,et al.  Molecular organization in micelles and vesicles. , 1981, Proceedings of the National Academy of Sciences of the United States of America.

[29]  H. C. Andersen.  Molecular dynamics simulations at constant pressure and/or temperature , 1980 .

[30]  G. Strobl,et al.  Phase transitions in crystals of chain molecules. Relation between defect structures and molecular motion in the four modifications of n-C33H68 , 1980 .

[31]  B. Lindman,et al.  Micelles. Physical chemistry of surfactant association , 1979 .

[32]  Thomas A. Weber,et al.  Simulation of n‐butane using a skeletal alkane model , 1978 .

[33]  Jean-Paul Ryckaert,et al.  Molecular dynamics of liquid alkanes , 1978 .

[34]  L. Staveley,et al.  Disorder in crystals , 1978 .

[35]  C. Windsor,et al.  Neutron quasi-elastic scattering of n-triacosane , 1977 .

[36]  G. Ciccotti,et al.  Numerical Integration of the Cartesian Equations of Motion of a System with Constraints: Molecular Dynamics of n-Alkanes , 1977 .

[37]  V. Schettino,et al.  Infrared and Raman Spectra and Polymorphism in Crystal n-Butane , 1975 .

[38]  Jacques Vieillard-Baron,et al.  The equation of state of a system of hard spherocylinders , 1974 .

[39]  A. Warshel,et al.  Consistent Force Field Calculations. II. Crystal Structures, Sublimation Energies, Molecular and Lattice Vibrations, Molecular Conformations, and Enthalpies of Alkanes , 1970 .

[40]  Donald E. Williams.  Nonbonded Potential Parameters Derived from Crystalline Hydrocarbons , 1967 .

[41]  L. Ehrenberg,et al.  The Crystal Structure of Lower Paraffins. IV. Refinement of the Crystal Structures of Pentane and Octane. , 1967 .

[42]  Harold A. Scheraga,et al.  Conformational Analysis of Macromolecules. II. The Rotational Isomeric States of the Normal Hydrocarbons , 1966 .

[43]  Monte Carlo study of rotational premelting in crystals of long chain paraffins , 1965 .

[44]  Y. Mnyukh.  Laws of phase transformation in a series of normal paraffins , 1963 .

[45]  A. Smith.  The Crystal Structure of the Normal Paraffin Hydrocarbons , 1953 .

[46]  A. Muller.  An X-Ray Investigation of Normal Paraffins Near Their Melting Points , 1932 .