Orientational properties of liquid-crystalline 4-n-alkyloxybenzilidene-4′-fluoroanilines

Abstract
The orientational order of 4-n-hexyloxybenzilidene-4′-fluoroaniline, (FAB-OC6) and its 4-n-heptyloxy analogue, (FAB-OC7), studied by means of 2H NMR and 19F NMR is reported. The entire temperature range of the liquid-crystalline phases (SB, SA and N for FAB-OC6, SB and SA for FAB-OC7) have been investigated. The results are discussed in relation to previous X-ray diffraction measurements. The chemical shift tensor components of the fluorine bond, evaluated from the 19F NMR spectra are compared with previous results.