Crystal engineering and [C-H•••O] hydrogen bonds at the organic/inorganic interface.: The bi-continuous hybrid composite, κ(2/3-3)-(EDT-TTF)8{[Ca(H2O)4]2(TeW6O24)•7H2O}2

The thirty water molecules in the compound formulation obtained by electrocrystallization are confined at the organic/inorganic interface where they become neatly organized as key components, together with the Anderson crown-anions, in the construction of a 2D coordination polymer within the first and second Ca2+ coordination spheres. They also serve as a relay for a set of [C-H ... O] interactions that ultimately organize the distribution of electrons within the ethylenedithiotetrathiafulvalenium (EDT-TTF) slabs, which adopts a novel tiling mode of the kappa slab. (C) Academie des sciences/Elsevier, Paris.