In a two-dimensional (2D) equilibrium Lennard--Jones (LJ) liquid, coarse-grained time-averaged spatial distribution of local solid-like structures is studied in order to estimate the hypothetical local-structure-based long time scale. Standard NVE molecular dynamics simulation method is used. Time-averaged distributions indicate a structural slow mode with a characteristic time-scale at least two orders of magnitude larger than the local oscillation period.

PACS numbers: 61.20.Ja, 64.70.Dv