We describe a mixture thin film as a membrane endowed with multiple out-of-tangent-plane vectors at each point, with vector sequence defined to within a permutation to account for the mixing of the mixture components.Such a description is motivated by a proposal for an atomistic-to-continuum derivation of a representation of multiatomic layer thin films, a view not requiring the introduction of phenomenological parameters. Differences between that proposal and the model discussed here are the definition of the values of the layer-descriptor map to within permutations and the explicit introduction of a bending-like term in the energy. The out-of-tangent-plane vectors satisfy a condition forbidding them to fall within the tangent plane after deformation.We consider a generic weakly surface-polyconvex membrane energy and a quadratic bending term involving the out-of-tangent-plane multiple vectors, a term which is also quasiconvex. Under appropriate energy growth assumptions and Dirichlet-type boundary conditions, we prove existence of ground states, i.e., equilibrium configurations described by the solutions to balance equations.An obvious corollary is the existence of equilibrium configurations of single out-of-tangent-plane vector Cosserat surfaces, a natural scheme for plates of simple materials.