  We report on a comprehensive computer simulation study of the liquid-crystal
phase behaviour of purely repulsive, semi-flexible rod-like particles. For the
four aspect ratios we consider, the particles form five distinct phases
depending on their packing fraction and bending flexibility: the isotropic,
nematic, smectic A, smectic B and crystal phase. Upon increasing the particle
bending flexibility, the various phase transitions shift to larger packing
fractions. Increasing the aspect ratio achieves the opposite effect. We find
two different ways how the layer spacing of the particles in the smectic A
phase may respond to an increase in concentration. The layer spacing may either
decrease or increase depending on the aspect ratio and flexibility. For the
smectic B and the crystalline phases, increasing the concentration always
decreases the layer spacing. We find that the layer spacing jumps to a larger
value on transitioning from the smectic A to the smectic B phase.
