  We report molecular dynamics simulation studies addressing the effects of
pore connectivity on the dynamics of two representative fluids CO$_2$ and
ethane in silicalite by systematically varying the degree of pore connectivity
through selectively blocking some pore space with immobile methane molecules.
By selectively turning off the pore spaces in the shape of straight, or
tortuous zigzag channels, we also probe the effects of pore tortuosity. In
general, pore connectivity is found to facilitate both the translational as
well as rotational dynamics of both fluids, while the intermolecular modes of
vibration in both fluids remain largely unaffected. The effects of providing
connections between a set of straight or zigzag channel-like pores are however
more nuanced. Pore tortuosity facilitates the rotational motion, but suppresses
the translational motion of CO$_2$, while its effects on the rotational and
translational motion of ethane are less pronounced. The intermolecular
vibrational modes of both fluids shift to higher energies with an increase in
the number of tortuous pores. The results reported here provide a detailed
molecular level understanding of the effects of pore connectivity on the
dynamics of fluids and thus have implications for applications like fluid
separation.
