  A number of stellar open cluster (OC) pairs in the Milky Way occupy similar
positions in the phase space (coordinates, parallax and proper motions) and
therefore may constitute physically interacting systems. The characterization
of such objects based on observational data is a fundamental step towards a
proper understanding of their physical status and to investigate cluster pair
formation in the Galaxy. In this work, we employed Gaia EDR3 data to
investigate a set of 16 OCs distributed as seven stellar aggregates. We
determined structural parameters and applied a decontamination technique that
allowed to obtain unambiguous lists of member stars. The studied OCs span
Galactocentric distances and ages in the ranges ~7 < $R_G$ (kpc) < ~11 and 7.3
<= log t <= 9.2. Eight OCs were found to constitute 4 gravitationally bound
pairs (NGC5617-Trumpler22, Collinder394-NGC6716, Ruprecht100-Ruprecht101,
NGC659-NGC663, the latter being a dynamically unevolved binary) and other 4
clusters constitute 2 interacting, but gravitationally unbound, pairs
(King16-Berkeley4, NGC2383-NGC2384, the latter being a dissolving OC). Other 4
OCs (Dias1, Pismis19, Czernik20, NGC1857) seem not associated to any stellar
aggregates. Apparently, clusters within bound and dynamically evolved pairs
tend to present ratios of half-light to tidal radius larger than single
clusters located at similar $R_G$, suggesting that mutual tidal interactions
may possibly affect their structural parameters. Unbound or dynamically
unevolved systems seems to present less noticeable signature of tidal forces on
their structure. Moreover, the core radius seems more importantly correlated
with the clusters' internal dynamical relaxation process.
