Anisotropic self-diffusion in the nematic phase of a thermotropic liquid crystal by H-1-spin-echo nuclear magnetic resonance
2001 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 115, no 4, 1946-1950 p.Article in journal (Refereed) Published
The orientation-dependent molecular diffusion in the nematic liquid crystal 4-pentyl-4'-cyanobiphenyl is measured to high accuracy. The applied nuclear magnetic resonance method combines multiple-pulse homonuclear dipolar decoupling with pulsed-field-gradient stimulated echo and slice selection. The obtained temperature dependencies of the principal diffusion coefficients are not described by a simple Arrhenius relationship but reflect the decrease of the molecular orientational order close to the nematic-to-isotropic phase transition. The geometric average of the principal diffusion coefficients is continuous with the diffusion coefficient in the isotropic phase. The results are best described in terms of the affine transformation model of diffusion in hard-ellipsoid nematics.
Place, publisher, year, edition, pages
2001. Vol. 115, no 4, 1946-1950 p.
studying translational diffusion, multiple-pulse nmr, pgse nmr, stimulated-echo, scattering, dynamics, water, tool
IdentifiersURN: urn:nbn:se:kth:diva-20780ISI: 000169800000035OAI: oai:DiVA.org:kth-20780DiVA: diva2:339477
QC 201005252010-08-102010-08-10Bibliographically approved