Fig. 1.

Sketch of the chain molecule. The backbone is modeled as a chain of (dark color) spheres of radius a with a separation along the chain l = 3.8 Å. The nearest-neighbor spheres along the backbone are allowed to overlap with each other, thereby overtly introducing uniaxial anisotropy. t_i and n_i are the tangent and normal vectors assigned to each sphere i, except to those at the ends of the chain. Side spheres (shown in light color) of radius b are attached to the backbone spheres in the negative normal direction. The side spheres are not allowed to overlap with either the backbone spheres or with each other.