2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/103073Oscillatory density profiles (layers) have previously been observed at the free surfaces of liquid metals, but not in other isotropic liquids. We have used x-ray reflectivity to study a molecular liquid, tetrakis(2-ethylhexoxy)silane. When cooled to T/Tc~0.25 (well above the freezing point for this liquid), density oscillations appear at the surface. Lateral order within the layers is liquid-like. Our results confirm theoretical predictions that a surface-layered state will appear even in dielectric liquids at sufficiently low temperatures, if not preempted by freezing.accepted for publication in Phys. Rev. Lett. 15 pages 4 figuresSoft Condensed Mattertext