10.1021/acs.jpcc.5b09537.s001 Michael F. Harrach Michael F. Harrach Barbara Drossel Barbara Drossel Wadim Winschel Wadim Winschel Torsten Gutmann Torsten Gutmann Gerd Buntkowsky Gerd Buntkowsky Mixtures of Isobutyric Acid and Water Confined in Cylindrical Silica Nanopores Revisited: A Combined Solid-State NMR and Molecular Dynamics Simulation Study American Chemical Society 2015 microphase separation Water Confined simulations show Molecular Dynamics Simulation StudyThe phase behavior isobutyric acid water concentration increases NMR spectroscopy entropic contributions combination material phase behavior Cylindrical Silica Nanopores Revisited pore wall SBA MD simulations pore surface 2015-12-31 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Mixtures_of_Isobutyric_Acid_and_Water_Confined_in_Cylindrical_Silica_Nanopores_Revisited_A_Combined_Solid_State_NMR_and_Molecular_Dynamics_Simulation_Study/2093425 The phase behavior of a mixture of isobutyric acid and water confined in mesoporous SBA-15 silica material is studied by a combination of solid-state NMR spectroscopy and molecular dynamics (MD) simulations. The combination of these two techniques shows that the iBA-rich phase is close to the pore wall and the water-rich phase is in the center of the pores. The MD simulations reveal that this surprising phase behavior is mainly the result of the minimization of the hydrogen-bonding enthalpy. Moreover, the simulations show also that upon increasing temperature the relative water concentration increases at the pore surface, which is attributed to entropic contributions which lead to a more thorough miscibility. These results solve a long-standing problem of the microphase separation inside these materials.