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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
A New, More Stable Polymorphic Form of Otilonium Bromide: Solubility, Crystal Structure, and Phase Transformation
Daniel R Vega1, Emilia Halac1, Luciano Segovia2
1Gerencia de Investigación y Aplicaciones, Centro Atómico Constituyentes, Comisión Nacional de Energía Atómica, Buenos Aires, Argentina; Escuela de Ciencia y Tecnología, Universidad Nacional General San Martín, Buenos Aires, Argentina.
Abstract:
A new polymorphic form of otilonium bromide is presented (Form I), and a thorough analysis of its crystal and molecular structure is performed. The compound suffers a temperature-driven first-order phase transition at about 396 K, which transforms it into the polymorph reported by Dapporto P and Sega A (Acta Cryst. 1986;C42:474-478) (Form II). Through thermal analysis and solubility experiments the relative stability of both crystal modifications were determined, confirming that at room temperature this new Form I is the more stable one, Form II existing just in a metastable state.
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