Type IIB on S3 x S3 through Q & P fluxes

We study a class of orientifold compactifications of type IIB supergravity with fluxes down to 4D in connection with truncations of half-maximal gauged supergravities yielding isotropic STU-models with minimal supersymmetry. In this context, we make use of a group-theoretical approach in order to derive flux-induced superpotentials for differ ent IIB backgrounds. We first review the toroidal case yielding GKP-like superpotentials characterised by their no-scale behaviour. We then turn to S 3 × S 3 and S 3 × T 3 , which, surprisingly, give rise to effective descriptions of non-geometric Q- and P-fluxes through globally geometric non-toroidal compactifications. As a consequence, such constructions break the no-scale symmetry without invoking any non-perturbative effects.