Molecular crystals and liquid crystals science technology. Section A, Molecular crystals and liquid crystals/Molecular crystals and liquid crystals science and technology. Section A, Molecular crystals and liquid crystals · 1997 · 11 citations · 7 references
Natural SciencesChemistryPhysicsCondensed Matter PhysicsPhysical ChemistrySolid State PhysicsCrystallization ProcessesLiquid CrystalsPhase DiagramsPhase EquilibriaPhase TransitionsSolid-state Phase TransitionsCrystalline StructureEnthalpyHigh-temperature Phase RelationsLiquid Crystal Phase BehaviorLiquid Crystal Phase TransitionsLiquid CrystallizationTemperature Effects On Phase BehaviorX-ray Diffraction Analysis
Abstract Phase situation of didodecyldimethylammonium bromide (DDAB) was investigated by means of differential scanning calorimetry. X-Ray diffraction and optical microscopy methods. A complex polymorphism was detected. Apart from the crystalline phase on heating there are two liquid crystalline phases below the isotropic liquid and on cooling a third phase appears. The study shows that DDAB exhibits highly ordered layered liquid crystalline structures. The high-temperature phase which appears below the isotropic phase can be identified as SmB phase. The influence of thermal history the polymorphism of DDAB was studied. The enthalpy changes at the transitions were calculated.
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Biomineralization and biomimetic materials chemistry
Stephen Mann · Journal of Materials Chemistry · 1995 · 244 citations