|Table of Contents|

Phase Transitions From Isotropic to Biaxial Phase of Cross-Like Nematic Liquid Crystal Molecules(PDF)

《南京师大学报（自然科学版）》[ISSN:1001-4616/CN:32-1239/N]

Issue:
2011年02期
Page:
39-44
Research Field:
物理学
Publishing date:

Info

Title:
Phase Transitions From Isotropic to Biaxial Phase of Cross-Like Nematic Liquid Crystal Molecules
Author(s):
Wang Huanjing; Liu Hong
School of Physics and Technology,Nanjing Normal University,Nanjing 210046,China
Keywords:
b iax ia l nem a tic liqu id cry sta ; l phase transition;  m olecu lar interaction
PACS:
O753.2
DOI:
-
Abstract:
A system com po sed o f cro ss- like nema tic liqu id cry sta lm o lecules is cons idered. Suppo se them o lecular interac tion is the superposition o f interactions am ongm o lecular rods, and the streng ths of inte ractions are independent. W ithin the m ean field theory, three types o f phase d iag ram s in the p lane o f temperature and them o lecular structure param eters are obta ined. In the first type of phase diag ram, there appears only one Landau po int a tw hich system enter d irec tly from isotropic to b iax ial phase by second orde r phase transition. In the second type, Landau po int becom es a Landau curv ew here sy stem ente rs from iso trop ic to biax ia l phase by first order phase trans ition. In the th ird type, the Landau curv e still ex ists, bu tw ith in a sm alle r range. The above phase d iagram s show tha t the types o f phase transitions and occurrence o f Landau curve depend on the va lues of m olecular interaction streng ths

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Last Update: 2011-06-15