  Hard sphere suspensions are well recognized model systems of statistical
physics and soft condensed matter. We here investigate the temporal evolution
of the immediate environment of nucleating and growing crystals and/or their
global scale distribution using time resolved Small Angle Light Scattering
(SALS). Simultaneously performed Bragg scattering (BS) measurements provide an
accurate temporal gauging of the sequence of events. We apply this approach to
studies of re-crystallization in several different shear molten hard sphere and
attractive hard sphere samples with the focus being on the diversity of
observable signal shapes and their change in time. We demonstrate that
depending on the preparation conditions different processes occur on length
scales larger than the structural scale which significantly influence both the
crystallization kinetics and the final micro-structure. By careful analysis of
the SALS signal evolution and by comparing different suggestions for small
angle signal shapes to our data we can for most cases identify the processes
leading to the observed signals. These include phase contrast form factor
scattering from depletion zones during formation and overlap as well as during
gelation, amplitude contrast form factor scattering by more transparent
crystals, and structure factor scattering from late stage inter-crystallite
ordering. The large variety of different small angle signals thus in principle
contains valuable information complementary to that gained from Bragg
scattering or microscopy. Our comparison, however, also shows that further
refinement and adaptation of the theoretical expressions to the sample specific
boundary conditions is desired for a quantitative kinetic analysis of
micro-structural evolution.

Soft Condensed Matter