Transferable MARTINI Model of Poly (ethylene Oxide)

Citation (APA 7)

Grunewald, F., Rossi, G., De Vries, A. H., Marrink, S. J., & Monticelli, L. (2018). Transferable MARTINI model of poly (ethylene oxide). The journal of physical chemistry B, 122(29), 7436-7449.

Abstract

Motivated by the deficiencies of the previous MARTINI models of poly(ethylene oxide) (PEO), we present a new model featuring a high degree of transferability. The model is parametrized on (a) a set of 8 free energies of transfer of dimethoxyethane (PEO dimer) from water to solvents of varying polarity; (b) the radius of gyration in water at high dilution; and (c) matching angle and dihedral distributions from atomistic simulations. We demonstrate that our model behaves well in five different areas of application: (1) it produces accurate densities and phase behavior or small PEO oligomers and water mixtures; (2) it yields chain dimensions in good agreement with the experiment in three different solvents (water, diglyme, and benzene) over a broad range of molecular weights (∼1.2 kg/mol to 21 kg/mol); (3) it reproduces qualitatively the structural features of lipid bilayers containing PEGylated lipids in the brush and mushroom regime; (4) it is able to reproduce the phase behavior of several PEO-based nonionic surfactants in water; and (5) it can be combined with the existing MARTINI PS to model PS–PEO block copolymers. Overall, the new PEO model outperforms previous models and features a high degree of transferability.