Determination of Phase Transitions of <i>p</i>,<i>n</i>-Alkyloxy Benzoic Acid Mesogens Using Legendre Moments and Image Analysis

• 作者: C. Nageswara Rao Ha Sie Tiong K. Mallika S. Lakshminarayan S. Sreehari Sastry
• 来源期刊: 凝固态物理国际期刊(英文)
• 学科: 化学
• 关键词: Alkyloxybenzoic Acids Homeotropic Alignment Phase Transitions Textures Legendre Moments Image ANALYSIS
• 年，卷（期）: ngtwlgjqkyw_2013,（1）
• 页码范围: 54-61
• 页数: 8页
• 分类号: O6

摘要

Phase transition temperatures of p,n-alkyloxy benzoic acids (nOBA, n = 3 to 10 and 12) are investigated basing on the textural image analysis of liquid crystal. The analysis is carried out by the computation of Legendre moments. Textures of the homeotropically aligned compounds are recorded as a function of temperature using POM in arthroscopic mode attached to the hot stage and high resolution camera. A recurrence formula is used to compute the liquid crystal textures based on Legendre polynomial. The discontinuities and fluctuations in the values of Legendre moments as a function of temperature are related to the phase transition temperatures of the sample. This method is successful in conforming or detecting the phase transition temperatures and the present findings are comparable with literature.