02197nas a2200253   4500008004100000022001400041245013900055210006900194260008600263300001400349490000700363520124800370653002001618653002501638653002101663653001701684653002301701653001801724653001901742653001201761100002601773700002301799856012101822       2012                        eng d  a0022-234800aPrediction of structure and energy of trans-1,4-polybutadiene glassy surface by atomistic simulations of free-standing ultrathin films0 aPrediction of structure and energy of trans14polybutadiene glass  a325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USAbTAYLOR & FRANCIS INCcMAR  a2201-22210 v513 a<p>Atomistic modeling of amorphous trans-1,4-polybutadiene (TPBD), using molecular mechanics and molecular dynamics (MD) simulations, is performed to generate three-dimensionally periodic bulk and two-dimensionally periodic thin film condensed phases. The condensed structures are constructed using multiple polymer chains. Structural and energetic relaxations and sampling of properties are performed using MD in the canonical ensemble (NVT) by a procedure that relieves local high-energy spots and brings the system to realistic thermodynamic states. The calculated surface energy for TPBD, 30.72 erg/cm(2), is in excellent agreement with the reported experimental value of 31 erg/cm(2). The structure of the surface layers is probed in terms of the atomic mass density variations, bond-bond orientation function profiles, and the distribution of the dihedral angles about the rotatable backbone bonds. The thickness of the surface layer over which the density varies smoothly but rapidly is found to be approximately 15 angstrom. The level of agreement of the calculated surface energy with the experimental value is superior in comparison to previous investigations in the literature using the atomistic approach for flexible polymers.</p>10a4-polybutadiene10aatomistic simulation10abond-orientation10aConformation10amolecular dynamics10apolymer glass10asurface energy10atrans-11 aIjantkar, Ashwini, S.1 aNatarajan, Upendra  uhttps://library.ncl.res.in/content/prediction-structure-and-energy-trans-14-polybutadiene-glassy-surface-atomistic-0