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Nematic phase

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Nematic phase for the hard 6x1x1 ellipsoid model.

The nematic phase of a liquid crystal has orientational order, but no positional order [1].

Dielectric tensor[edit]

In the uniaxial nematic phase, defining the z-axis to be parallel to the nematic axis, one has

\epsilon_{\alpha \beta}= \begin{pmatrix}
  \epsilon_\bot & 0               & 0 \\
  0             &  \epsilon_\bot  & 0 \\
  0             &  0              & \epsilon_\|

The anisotropy is defined as

\Delta \epsilon = \epsilon_\| - \epsilon_\bot .

The response of a nematic liquid crystal to an external electric field depends on both the sign and the magnitude of \Delta \epsilon.

Chiral nematic phase[edit]

See Chiral phases.

Discotic nematic phase[edit]

Discotic-nematic phase for the hard 6x6x1 ellipsoid model.

Biaxial nematic phase[edit]