4’- uniaxial rigid body

The transformation from the MOL to the RIG reflects the overall rotation of the molecule around its long axis. If the molecule rotates along the axis with more than threefold symmetry, indicating that it is regarded as being a uniaxial rigid body, then... 

Safely, 60CB molecule can be regarded as a uniaxial rigid body, and therefore, biaxial properties of the molecule are ignored for this coordinate transformation, although the biaxiality of the phase expressed by Eq. (9) was additionally required for simulating stationary NMR spectra for 60CB in cholesteric LC phases, which will be discussed in the later section. 

In physical terms, the distance between material planes that are perpendicular to the flow direction increases in extensional flow. This is illustrated for uniaxial extension in Figure 14.11a. A material plane is a surface that always contains the same material points or particles. In viscometric flow, the fluid on any surface for which the coordinate X2 is a constant forms a material plane (see Figure 14.11b). Here, each material plane moves as a rigid body and there is... 

FIGURE 4 Theoretical compression cycles under uniaxial compression within a rigid frictionicss die (A) Perfect elastic body (B) body with constant yield stress in shear and (C) Mt r s body. Source Adapted from Ref. 19. 

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