  There is growing evidence that slow dynamics and dynamic heterogeneity
possess structural signatures in glass-forming liquids. However, even in the
weakly frustrated glass-forming liquids, whether or not the dynamic
heterogeneity has a structural origin is a matter of debate. Via molecular
dynamics simulation, we present a study of examining the connection between
dynamic heterogeneity and bond orientational order in a weakly frustrated
glass-forming liquid in two dimensions by taking advantage of assessing the
effect of attractions on the correlation length scales. We find that
attractions can strongly affect relaxation dynamics, dynamic heterogeneity and
the associated dynamic correlation length of the liquid, but their influence on
bond orientational order and the associated static correlation length shows a
manner reminiscent of the effect of attractions on the thermodynamics of
liquids. This implies that the growth of bond orientational order and static
correlation length scale might be merely a manifestation of favoring the
configurational entropy in weakly frustrated glass-forming liquids. Thus, our
results lead strong evidence that bond orientational order cannot provide a
complete description of dynamic heterogeneity even in weakly frustrated
glass-forming systems.
