# softmatter:Nematic Order Parameter

From NSDL Materials Digital Library Wiki

One can measure the degree of order in a rod like system by using the following order parameter [1,2]:

where theta is the angle with respect to the director (average direction of the rods) in the system. Typically values of the order parameter [1,2]:

- Crystal: S~1
- Disordered liquids: S<0.3
- Liquid crystals: S~0.3-0.9