Dye induced reorientation in methyl red-E7 guest-host system

Authors

  • Rasmia M. Lalanto ⋅ PH National Institute of Physics, University of the Philippines Diliman
  • Anthony G. Montecillo ⋅ PH National Institute of Physics, University of the Philippines Diliman
  • Marlon Rosendo H. Daza ⋅ PH National Institute of Physics, University of the Philippines Diliman
  • Manuela Fe H. Tarroja-Keller ⋅ PH National Institute of Physics, University of the Philippines Diliman
  • Leonorina G. Cada ⋅ PH Institute of Chemistry, University of the Philippines Diliman
  • Zenaida B. Domingo ⋅ PH National Institute of Physics, University of the Philippines Diliman

Abstract

The effect of dye concentration in methyl red-E7 guest-host system was investigated for two cases: without illumination and with illumination. A theoretical model based on Jones matrix calculus was also formulated and it revealed sine-squared birefringence patterns similar to experimental transmission profiles. Phase retardation and phase shift calculations from transmission measurements were also observed to very with dye concentration. Polarized UV-Vis spectra of cells revealed an increasing order parameter with increasing dye concentration until c = 1.25%, above which, the order parameter was observed to decrease considerably as may be effected by a phase separation. Results suggest that dye concertation significantly affects level of ordering in dye-doped liquid crystals (DDLCs) even prior to illumination. Cell illumination with Ar+ beam revealed a higher level of ordering after relaxation due to a laser-induced reorientation driven by the trans-cis photoisomerization of methyl red in the green wavelength range.

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Published

1997-10-27

How to Cite

[1]
RM Lalanto, AG Montecillo, MRH Daza, MFH Tarroja-Keller, LG Cada, and ZB Domingo, Dye induced reorientation in methyl red-E7 guest-host system, Proceedings of the Samahang Pisika ng Pilipinas 15, SPP-1997-OP-12 (1997). URL: https://proceedings.spp-online.org/article/view/SPP-1997-OP-12.