Roke, S.Buitenhuis, J.Van Miltenburg, J. C.Bonn, M.Van Blaaderen, A.2013-02-082013-02-082013-02-08200510.1088/0953-8984/17/45/0362-s2.0-27744464017https://infoscience.epfl.ch/handle/20.500.14299/88720We have compared calorimetric measurements with the nonlinear optical technique vibrational sum frequency scattering to investigate interface-solvent effects in colloidal gelation transitions. This allows us to explain the difference in gelation behaviour between dispersions of stearyl-coated silica particles in n-hexadecane and benzene or toluene. In n-hexadecane dispersions, an anomalous heat effect is observed, due to the formation of an ordered interface layer (that is not confined to the first monolayer and is composed of ∼1/3 surface crafted chains and ∼2/3 solvent molecules). For solvents that cannot interdigitate with the surface chains this transition does not occur and consequently no heat effect is observed. © 2005 IOP Publishing Ltd.text::journal::journal article::research article