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Phase transitions and self-assemblies of lower diamondoids and derivatives

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 نشر من قبل G.Ali Mansoori
 تاريخ النشر 2018
  مجال البحث فيزياء
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Applying ab initio calculation and molecular dynamics simulation methods, we have been calculating and predicting the essential self-assemblies and phase transitions of two lower diamondoids (adamantane and diamantane), three of their important derivatives (amantadine, memantine and rimantadine), and two organometallic molecules that are built by substituting one hydrogen ion with one sodium ion in both adamantane and diamantine molecules (ADM-Na and Optimized DIM-Na). To study their self-assembly and phase transition behaviors, we built seven different MD simulation systems, and each system consisting of 125 molecules. We obtained self-assembly structures and simulation trajectories for the seven molecules. Radial distribution function studies showed clear phase transitions for the seven molecules. Higher aggregation temperatures were observed for diamondoid derivatives. We also studied the density dependence of the phase transition which demonstrates that the higher the density - the higher the phase transition points.



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We report self-assembly and phase transition behavior of lower diamondoid molecules and their primary derivatives using molecular dynamic (MD) simulation and density functional theory (DFT) calculations. Two lower diamondoids (adamantane and diamanta ne), three adamantane derivatives (amantadine, memantine and rimantadine) and two artificial molecules (Adamantane+Na and Diamantane+Na) are studied separately in 125-molecule simulation systems. We performed DFT calculations to optimize their molecular geometries and obtain atomic electronic charges for the corresponding MD simulation, by which we obtained self-assembly structures and simulation trajectories for the seven molecules. Radial distribution functions and structure factors studies showed clear phase transitions for the seven molecules.
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