Study of Refractive Indices, Density and Order Parameters of Two Nematogens and Their Eutectic Mixture

• Authors: S. Datta Sarkar , B. Choudhury
• Languages of publication: EN

Abstracts

EN

The compounds 5-pentyl-2-(4'-cyanophenyl) pyrimidine [CM 7035] and 4-n-butyl-4'-ethoxytolan [PTP4O2] and mixtures of different mole fractions of them show nematic phase with supercooling effect. From the phase diagram the equimolar mixture is found to be the eutectic mixture. Temperature variation of the density and refractive indices (n_{o}, n_{e}) of the pure compounds and their eutectic mixture have been reported here. The density and birefringence values of the eutectic mixture are found to be less than that of pure compounds. However the average refractive index values of eutectic mixture almost coincide with those of CM 7035 which are much less than those of PTP4O2. The refractive indices and density values have been analyzed to obtain the orientational order parameters. Experimental order parameter values of the pure compounds and the eutectic mixture are compared with theoretical Maier-Saupe values. The possible reasons for disagreement between theoretical and experimental values for the pure compounds are discussed. The agreement between theoretical and experimental order parameters are fairly good for the eutectic mixture.

Keywords

EN

78.15.+e; 64.70.M-

Discipline

• 78.15.+e: Optical properties of fluid materials, supercritical fluids and liquid crystals(for reactions in supercritical fluids, see 82.33.De)
• 64.70.M-: Transitions in liquid crystals

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2010
• Volume: 118
• Issue: 4
• Pages: 665-669

Dates

published

2010-10

received

2010-04-08

(unknown)

2010-06-21

Contributors

author

S. Datta Sarkar

• Dept. of Physics, Karimganj College, Karimganj - 788710, India
• Dept. of Physics, N.I.T., Silchar - 788010, India

author

B. Choudhury

• Dept. of Physics, N.I.T., Silchar - 788010, India

References

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Identifiers

DOI

10.12693/APhysPolA.118.665