The Acid Deposition Control Title (IV) of the 1990 Clean Air Act Amendments calls for reductions in annual sulfur dioxide and nitrogen oxide emissions in order to “reduce the adverse effects of acid deposition,” without addressing emissions of ammonia. Ammonia is present in precipitation and aerosols as the ammonium cation, NH4. Ammonium is rich in nitrogen and together with nitrate comprises v...

The structure of the title compound, NH(4)(C(8)H(20)N)(3)[Mo(8)O(26)], is built up by discrete cations and anions, with two formula units in the asymmetric unit. The β-octa-molybdate anions are linked to the ammonium cations via N-H⋯O hydrogen bonding involving terminal oxide groups and to the tetra-ethyl-ammonium cations via weak C-H⋯O inter-actions.

The crystal structure of the title compound, NH4[In(HPO3)2], is built up from In(III) cations (site symmetry 3m.) adopting an octa-hedral environment and two different phosphite anions (each with site symmetry 3m.) exhibiting a triangular-pyramidal geometry. Each InO6 octa-hedron shares its six apices with hydrogen phosphite groups. Reciprocally, each HPO3 group shares all its O atoms with thre...