Proton and deuterium nuclear spin relaxation study of the SmA and SmC* phases of BP8Cl-d17 : a self-consistent analysis
Copyright © 2014 John Wiley & Sons, Ltd.
Veröffentlicht in: | Magnetic resonance in chemistry : MRC. - 1985. - 52(2014), 10 vom: 26. Okt., Seite 546-55 |
---|---|
1. Verfasser: | |
Weitere Verfasser: | , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2014
|
Zugriff auf das übergeordnete Werk: | Magnetic resonance in chemistry : MRC |
Schlagworte: | Journal Article NMR relaxation fast field-cycling liquid crystal molecular dynamics smectic phase spin-lattice relaxation |
Zusammenfassung: | Copyright © 2014 John Wiley & Sons, Ltd. A self-consistent analysis of proton and deuterium nuclear spin relaxation times in the smectic phases of a partially deuterated smectogen is presented here. Proton spin-lattice relaxation times T(1Z) were measured as a function of Larmor frequency over a range of 1 kHz to 300 MHz at selected temperatures. Deuterium spin relaxation times T(1Z) and T(1Q) were measured as a function of temperature at two different magnetic fields in the smectic A phase. The deuterium data provide dynamic parameters such as rotational diffusion constants and internal jump rates as well as the nematic order parameter S. The proton data are analyzed using a number of relaxation mechanisms, one of which is the molecular reorientation. It is found helpful in these latter analyses to use the nematic order parameter and to fix the contribution from molecular reorientations determined by the deuterium spin relaxation. The fits to the proton T(1) frequency and temperature dispersions by the remaining relaxation mechanisms such as layer undulations and translational self-diffusion will be discussed for the smectic A and chiral smectic C phases |
---|---|
Beschreibung: | Date Completed 22.05.2015 Date Revised 25.09.2014 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
ISSN: | 1097-458X |
DOI: | 10.1002/mrc.4107 |