A chromic molybdenum phosphate with a tunnel structure: hydrothermal synthesis and structure of (NH3CH2CH2NH3)(2) center dot (NH3CH2CH2NH2)(3)center dot[NaCr2Mo12O30(PO4)(HPO4)(4)(H2PO4)(3)]center dot 6H(2)O

A chromic molybdenum phosphate, (NH3CH2CH2NH3)(2).(NH3CH2CH2NH2)(3).[NaCr2M o12O30(PO4)(HPO4)(3)]. 6H(2)O, involving molybdenum present in V oxidation, has been hydrothermally synthesized and structurally characterized by sing le crystal X-ray diffraction and IR spectrum. Deep brown-red crystals are f ormed in the triclinic system, space group P (1) over bar, a = 12.067(2), b = 14.677(3), c = 21.290(2) Angstrom, alpha = 80.940(10)degrees, beta = 82. 960(10)degrees, gamma = 76.61(2)degrees. The structure of the title compoun d may be considered to be two [Mo6O15(HPO4)(H2PO4)(3)](5-) units bonded to a chromic atom, although several P-O groups are not protonated on account o f coordination with a Na+ cation. The one-dimensional tunnels were formed i n the solid of the title compound. (C) 2000 Elsevier Science B.V. All right s reserved.