  The problem of spin diffusion is studied numerically in one-dimensional
classical Heisenberg model using a deterministic odd even spin precession
dynamics. We demonstrate that spin diffusion in this model, like energy
diffusion, is normal and one obtains a long time diffusive tail in the decay of
autocorrelation function (ACF). Some variations of the model with different
coupling schemes and with anisotropy are also studied and we find normal
diffusion in all of them. A systematic finite size analysis of the Heisenberg
model also suggests diffusive spreading of fluctuation, contrary to previous
claims of anomalous diffusion.
