<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Positron annihilation studies of liquid crystals are reviewed with particular reference to thermotropic liquid crystals with rod-like molecules. The studies of compounds exhibiting smectic A or smectic E phases indicate that local arrangement of dipole molecules play an important role because high electron density at the end group of molecules can influence substantially formation and annihilation of positronium. The obtained <italic>ortho</italic>-positronium lifetimes in these phases can be explained by antiparallel pairing of molecules in case of the smectic A phase or a structure with a nanosegregation of alkyl chains and others parts of molecules into sublayers and liquid-like state of alkyl chains in case of the smectic E phase.</p></abstract>

Positron annihilation studies of liquid crystals are reviewed with particular reference to thermotropic liquid crystals with rod-like molecules. The studies of compounds exhibiting smectic A or smectic E phases indicate that local arrangement of dipole molecules play an important role because high electron density at the end group of molecules can influence substantially formation and annihilation of positronium. The obtained ortho-positronium lifetimes in these phases can be explained by antiparallel pairing of molecules in case of the smectic A phase or a structure with a nanosegregation of alkyl chains and others parts of molecules into sublayers and liquid-like state of alkyl chains in case of the smectic E phase.

Positron annihilation in liquid crystals

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{"article-title":"Positron annihilation in liquid crystals"}

Positron annihilation studies of liquid crystals are reviewed with particular reference to thermotropic liquid crystals with rod-like molecules. The studies of...

Positron annihilation in liquid crystals

Online veröffentlicht: 01. Dez. 2015

Seitenbereich: 703 - 708

Eingereicht: 25. Juni 2015

Akzeptiert: 25. Aug. 2015

DOI: https://doi.org/10.1515/nuka-2015-0125

Schlüsselwörter
liquid crystals, positron annihilation, phase transitions

© 2015 Ewa Dryzek et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Positron annihilation in liquid crystals

Online veröffentlicht: 01. Dez. 2015

Seitenbereich: 703 - 708

Eingereicht: 25. Juni 2015

Akzeptiert: 25. Aug. 2015

DOI: https://doi.org/10.1515/nuka-2015-0125

Schlüsselwörterliquid crystals, positron annihilation, phase transitions

© 2015 Ewa Dryzek et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Schlüsselwörter
liquid crystals, positron annihilation, phase transitions