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The effect of chain branching on glycolipid thermotropic and lyotropic phases was investigated for a series of synthetic β-D-glucosides derived from Guerbet alcohols, whose total hydrocarbon chain length ranged from C₈ to C₂₄. The compounds, which can be viewed as isosteric mimics for glycoglycerolipids, were synthesised in high purity and their liquid crystalline phases were studied using optical polarising microscopy (OPM), and small-angle X-ray diffraction. When dry, the shortest compound (total C₈) exhibits a monotropic L_α phase while longer ones (C₁₆ and C₂₀) adopt inverse hexagonal H_II phases. The C₂₄ compound forms an ordered lamellar phase at room temperature, but exhibits a metastable H_II phase upon cooling. Curiously the intermediate chain length homologue (C₁₂) adopts an isotropic inverse micellar (L₂) phase in the dry state over the range of temperatures studied. Upon hydration, the C …