Semi-flexible star-shaped molecules: conformational analysis of nano-segregated mesogens forming columnar liquid-crystal phases
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Sibylle Gemming
,
Matthias Lehmann
Abstract
The structural prerequisites are investigated, which make star-shaped molecules suitable precursors for the formation of columnar liquid-crystalline phases. Electronic structure calculations on smaller mesogens show that not all conformers exhibit the atomistic structure, the stability against distortion, and additional dipole moments, which favour columnar stacking. For the presently studied compounds with short terminating alkyl chains, the calculations indicate that the steric factor becomes dominant with increasing star size. Thus, the optimised geometric structures were employed to generate a simplified mathematical model of the structures, which accounts only for the steric interaction in the larger stars. With the help of these diagrams, the most common conformers of star-shaped molecules can be derived in a systematic fashion.
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© 2005 Carl Hanser Verlag, München
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Artikel in diesem Heft
- Frontmatter
- Kösterpreis
- Award/Preisverleihung
- Editorial
- Editorial
- Articles Basic
- Effect of interface strength on electromigration-induced inlaid copper interconnect degradation: Experiment and simulation
- Application of factor analysis in electron spectrometry (AES, XPS) for materials science
- Focussing and defocussing effects at radio frequency glow discharge optical emission spectroscopy analyses of thin films with partly nonconductive components
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- Articles Applied
- Structure, properties and applications of diamond-like carbon coatings prepared by reactive magnetron sputtering
- Local texture and back-end defect in hot extruded AZ91 magnesium alloy
- A comparison of thermal stability in nanocrystalline Ni- and Co-based materials
- Microstructure and phase formation of Heusler thin film compounds
- Correlation between the average composition of coherent superlattice and the GMR properties of electrodeposited Co–Cu/Cu multilayers
- Articles Basic
- Towards a description of complex pearlite structures
- Modeling of axial strain in free-end torsion of textured copper
- Vacancies in plastically deformed copper
- An analytic and generalized formulation of the sin2 ψ-method
- Nanoindentation applied on a tungsten–copper composite before and after high-pressure torsion
- Articles Applied
- The local deformation behaviour of MMCs – an experimental study
- X-ray elastic constants determined by the combination of sin2 ψ and substrate-curvature methods
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- Notifications/Mitteilungen
- Personal
