![Sample our Physical Sciences journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/110819/TOC-Subject-Sample-2021-Physical-Sciences.jpg"})
Abstract
The anisotropy of magnetic susceptibility of para-azoxy-anisole and of two related model compounds of main-chain nematic polymers (mono-methyl substituted on the phenyl rings) has been deduced from SQUID magnetometer measurements, and analyzed in terms of the theory of Horn and Faber2. For PAA, the results support our most recent analysis of NMR data 5 in which it was found that the anisotropy parameter ηs of the molecular orientational order varies between ∼ 0.1 and 0.3 throughout the nematic phase. For the two model compounds, η is probably much smaller, suggesting that their mesogenic units are more cylindrical in shape than PAA.