C-30 self-assembled monolayers (SAMs) have been prepared on zirconia, titania, and two different silica gels by reacting C-30 trichlorosilane with the humidified surfaces. C-13 solid-state NMR spectroscopy indicated higher alkyl chain order on titania and zirconia materials than on the silica C-30 phases. Order is inferred from the relative intensity of the main methylene carbon resonance assigned to an all-trans conformation. Carbon longitudinal relaxation time (T-1(C)) data reveal that these ordered alkyl chains still have large-amplitude motions on submicrosecond time scales at ambient temperature. Since fast diffusional rotation about the chain axis is compatible with an all-trans conformation, T-1(C), carbon chemical shift, and proton line width data for the alkane rotator phase (C-19) and the C-30 phases were compared. Proton spin diffusion experiments were also conducted using an initial polarization gradient based on mobility differences. These;experiments indicated both a higher mobility for the free end of the immobilized chains and heterogeneity in the density of coverage on at least the 20-nm distance scale. The methyl carbon line shape is also discussed in detail since its chemical shift conveys information about both mobility and interactions with an air interface in a dry sample. Atomic force microscopy and contact angle studies indicated a greater surface roughness for C-30 SAMs compared to C-18 SAMs prepared on silicon. Ellipsometry revealed film thicknesses of 2.82 nm for the C-18 SAM and 4.05 nm for the C-30 SAM. High shape selectivity was found in correspondent liquid chromatographic (LC) separations of polycyclic aromatic hydrocarbons, carotenoids, and tocopherols. The LC data confirm the highly organized alkyl chain arrangement on zirconia and titania, which provide an alternative to the silica-based reversed phases.