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Polymorphism of hydrogen-bonded star mesogens - a combinatorial DFT-D and FT-IR spectroscopy study.

ABSTRACT: A comprehensive study combining detailed computational analyses with temperature-variable FT-IR experiments was performed in order to elucidate the structure of the hydrogen-bonded liquid crystals based on phloroglucinol and azopyridine in their mesophase. Conformational analysis revealed three relevant conformers: star, λ- and E-shape. The results demonstrate an entropy-driven unfolding mechanism of the assembly. The stability of the conformers is given by intermolecular π-π and dispersion interactions of the azopyridine side chains. Correlating the calculated vibrational frequency with experimental FT-IR spectra suggests a λ-folded conformation of the assemblies as the predominant species in the mesophase.

SUBMITTER: Pfletscher M

PROVIDER: S-EPMC9061708 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Polymorphism of hydrogen-bonded star mesogens - a combinatorial DFT-D and FT-IR spectroscopy study.

Pfletscher Michael M Wysoglad Janek J Gutmann Jochen S JS Giese Michael M

RSC advances 20190314 15

A comprehensive study combining detailed computational analyses with temperature-variable FT-IR experiments was performed in order to elucidate the structure of the hydrogen-bonded liquid crystals based on phloroglucinol and azopyridine in their mesophase. Conformational analysis revealed three relevant conformers: star, λ- and E-shape. The results demonstrate an entropy-driven unfolding mechanism of the assembly. The stability of the conformers is given by intermolecular π-π and dispersion inte ...[more]

PMID: 35518674

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