Dynamical properties of liquid in nano-channels attractmuch interest because of their applications in engineering and biological systems. The transfer behavior of liquid confined within nanopores differs significantly from that in the bulk. Based on the simple quasicrystal model of liquid

analytical expressions of self-diffusion coefficient both in bulk and in slit nanopore are derived from the Stokes–Einstein equation and the modified Eyring's equation for viscosity. The local self-diffusion coefficient in different layers of liquid and the global self-diffusion coefficient in the slit nanopore are deduced fromthese expressions. The influences of confinement by porewalls

pore widths

liquid density

and temperature on the self-diffusion coefficient are investigated. The results indicate that the self-diffusion coefficient in nanopore increaseswith the porewidth and approaches the bulk value as the pore width is sufficiently large. Similar to that in bulk state

the self-diffusion coefficient in nanopore decreases with the increase of density and the decrease of temperature

but these dependences are weaker than that in bulk state and become evenweaker as the porewidth decreases. Thiswork provides a simplemethod to capture the physical behavior and to investigate the dynamic properties of liquid in nanopores.