Optical characterization of a biaxial nematic between uniaxial nematic lyotropic phases

Author(s)

Santos, O. R. ^{[1, 2]} ; Braga, W. S. ^{[1, 2]} ; Luders, D. D. ^{[1, 3]} ; Sampaio, A. R. ^[1] ; Kimura, N. M. ^[1] ; Simoes, M. ^[4] ; Palangana, A. J. ^[1]

Affiliation

^[1] Univ Estadual Maringa, Dept Fis, Maringa, Parana - Brazil

^[2] Univ Tecnol Fed Parana, Campo Mourao - Brazil

^[3] Univ Estadual Maringa, Dept Engn Agr, Cidade Gaucha - Brazil

^[4] Univ Estadual Londrina, Dept Fis, Londrina, Parana - Brazil

• Document type: Journal article
• Source: PHASE TRANSITIONS; v. 94, n. 6-8, p. 546-555, AUG 3 2021.
• Web of Science Citations: 1

Abstract

The biaxial nematic (N-B) phase bordered by two uniaxial nematic (discotic - N-D and calamitic - N-C) phases and the one between N-D phases are studied in potassium laurate (K-L), decanol (DeOH) and D2O mixture using conoscopic images. The sequences of phases (N-D -> N-B(+) -> N-B(-) -> N-C and N-D -> N-B(+) -> N-D) were optically characterized, where N-B(+) and N-B(-) are the biaxial positive and biaxial negative nematic phases, respectively. A new sequence of phases (N-D -> N-B(+) -> N-B(-) -> NB+ -> N-D) found in one line of the phase diagram positioned close to the interface with the NC phase was also optically confirmed through conoscopic images. The N-B(+) (N-B(-)) -> N-B(-) (N-B(+)) transition point was determined by means of image processing. In this review work, we emphasize the relevance of the optical characterization of an NB- phase inherent to the nature of this lyotropic material. (AU)

• FAPESP's process: 14/50983-3 - INCT 2014: complex fluids
• Grantee: Antonio Martins Figueiredo Neto
• Support Opportunities: Research Projects - Thematic Grants