Indium-doped gallophosphate NH4[NiGa1.84In0.16(PO4)3(H2O)2]: synthesis, X-ray crystal structure and IR spectroscopy

Abstract

NH 4 [NiGa 1.84 In 0.16 (PO 4 ) 3 (H 2 O) 2 ] orthophos phate was prepared through hydrothermal synthesis and analyzed by means of single crystal X-ray diffractometry. It was solved within C 2/ c monoclinic space group; a = 13.2483(8) Å, b = 10.2468(8) Å, c = 8.9033(7) Å, β = 108.637(1)°, V = 1145.27(15) Å 3 . Phosphorous atoms display tetrahedral arrangement, occupying two distinct sites; Ni atoms form NiO 4 (OH 2 ) 2 distorted octahedra, while Ga and In atoms share the same site forming (Ga,In)O 5 units with trigonal bipyramidal geometry. (Ga,In)O 5 , NiO 4 (OH 2 ) 2 and PO 4 units are linked together through edge- and vertex-sharing arrangements, making up the three-dimensional framework, completed by (NH 4 ) + counter-ions. Strong O—H…O and N—H…O hydrogen bonds contribute to stabilize the array: O—H…O interactions were also investigated by means of Libowitzky formula (Libowitzky, 1999) application, owing to the results of IR spectroscopy.