Mixtures of a bent-core mesogen (ClPbis10BB) and a calamitic mesogen (6OO8), showing a nematic phase over the entire compositional range and one or two smectic phases (namely, SmA, SmC, or SmCA) below the nematic one over a wide concentration range, were investigated by means of 2H NMR spectroscopy, exploiting selectively deuterated isotopomers of both mesogens. The analysis of 2H NMR spectra recorded in the liquid crystalline phases on several representative mixtures gave information on the orientational order properties and the molecular organization within the phases as well as on the alignment properties upon application of a magnetic field. On the other hand, the analysis of 2H longitudinal relaxation times (T1Z and T1Q) in 6OO8- d2/ClPbis10BB mixtures and pure 6OO8-d2 allowed the influence of the bent-core mesogen on the dynamics of the calamitic one to be highlighted.
Orientational Order, Molecular Organization, and Dynamics in Mixtures of Bent-Core and Rod-Shaped Mesogens: A H-2 NMR Study
GEPPI, MARCO
2011-01-01
Abstract
Mixtures of a bent-core mesogen (ClPbis10BB) and a calamitic mesogen (6OO8), showing a nematic phase over the entire compositional range and one or two smectic phases (namely, SmA, SmC, or SmCA) below the nematic one over a wide concentration range, were investigated by means of 2H NMR spectroscopy, exploiting selectively deuterated isotopomers of both mesogens. The analysis of 2H NMR spectra recorded in the liquid crystalline phases on several representative mixtures gave information on the orientational order properties and the molecular organization within the phases as well as on the alignment properties upon application of a magnetic field. On the other hand, the analysis of 2H longitudinal relaxation times (T1Z and T1Q) in 6OO8- d2/ClPbis10BB mixtures and pure 6OO8-d2 allowed the influence of the bent-core mesogen on the dynamics of the calamitic one to be highlighted.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
