  In this paper, we analyze the effect of geometrical constraint on the
conformational properties of an infinitely long linear semiflexible polymer
chain confined in-between two constraints under good solvent condition in two
dimensions. The constraints are two impenetrable stair shaped surface and for
two dimensional space, the surface is a one dimensional line. The
semiflexibility of the chain is accounted by introducing a Boltzmann weight of
bending energy required to produce each turn in the chain and good solvent
condition was accounted by using self avoiding walk model of the chain. We have
calculated exact critical value of step fugacity required for polymerization of
an infinitely long polymer chain confined in between the constraints for
different values of separation between the constraints for directed version of
the model. We have also calculated possible maximum, minimum values of the
persistent length for such chains and the maximum value of bending energy
required for each turn in the chain for few values of separation between the
constraints.
