“…In this second part and the upcoming third part [7], we complete this qualitative result by investigating more precisely the examples given by the primitive groups (see [5, §2] for the definition), i.e. the groups G 28 , G 29 , G 30 and G 31 (as in [5], we follow Shephard-Todd numbering for complex reflection groups [24]). In particular, we investigate the following questions:…”