Nematic phase

Nematic phase for the hard 6x1x1 ellipsoid model.

The nematic phase has orientational order, but no positional order.

[edit] Discotic nematic phase

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

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

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

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 $Δε$ .