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The properties of alkanes are consequential for understanding many chemical processes in nature and industry. We use molecular dynamics simulations with the Amber force field GAFF2 to examine the structure of pure liquids at each respective normal boiling point, spanning the 15 n-alkanes from methane to pentadecane. The densities predicted from the simulations are found to agree well with reported experimental values, with an average deviation of 1.9%. The enthalpies of vaporization have an average absolute deviation from experiment of 10.4%. Radial distribution functions show that short alkanes have distinct local structures that are found to converge with each other with increasing chain length. This provides a unique perspective on trends in the n-alkane series and will be useful for interpreting similarities and differences in the n-alkane series as well as the breakdown of ideal solution behavior in mixtures of these molecules. 

The A. aeolicus intrinsically disordered protein FlgM has four well-defined α-helices when bound to σ 28 , but in water FlgM loses structure. In this work, we investigate the structure of FlgM in aqueous solutions of the ionic liquid [C 4 mpy][Tf 2 N]. We find that FlgM is induced to fold by the addition of the ionic liquid, achieving average α-helicity values similar to the bound state. Analysis of secondary structure reveals significant similarity with the bound state, but the tertiary structure is found to be more compact than the bound state. Interestingly, the ionic liquid is not homogeneously dispersed in the water, but instead aggregates near the protein. Separate simulations of aqueous ionic liquid do not show ion clustering, which suggests that FlgM stabilizes ionic liquid aggregation.