2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/25605This is a short review of recent x-ray diffraction studies of the phases and phase transitions of thermotropic liquid crystals. The areas covered are twist-grain-boundary phases, antiferroelectric phases studied with resonant x-ray diffraction, and smectic phases within gel structures. In all areas x-ray diffraction has played a key role. Nonetheless open questions remain: the nature of the smectic-C variant of the twist-grain-boundary phase, the origin of antiferroelectric phases, and whether novel Bragg glass states exist for smectic-A gel samples.12 pages, 7 figuresSoft Condensed Mattertext