We give a general construction which shows that a large class of quantum complete intersections can be realized as the basic algebras of non-principal blocks of finite groups. We investigate the Ext rings of these algebras. We describe how to construct a finite p'-covering for one of these quantum complete intersections, which supports a Hopf algebra structure which is neither commutative nor cocommutative in general. We use this to investigate a problem concerning the definition of nucleus for a non-principal block.
- quantum groups