Hydrothermal Syntheses, Structural Characterizations, and Photoluminescence Properties of Three Fluorinated Indium Phosphates with Bipyridyl Ligands:  In₃F₂(2,2‘-bipy)₂(HPO₄)₂(H_1.5PO₄)₂, In₂F₂(H₂O)(2,2‘-bipy)(HPO₄)₂, and In₂F₂(H₂O)(2,2‘-bipy-5-amine)(HPO₄)₂

Abstract

Three novel fluorinated indium phosphates with the formulas In3F2(2,2‘-bipy)2(HPO4)2(H1.5PO4)2 (1), In2F2(H2O)(2,2‘-bipy)(HPO4)2 (2), and In2F2(H2O)(2,2‘-bipy-5-amine)(HPO4)2 (3) have been prepared hydrothermally in the presence of 2,2‘-bipy and 2,2‘-bipy-5-amine ligands. Single-crystal X-ray diffraction analysis reveals that 1 possesses an unusual neutral chained structure, which is not only the first 1D chain in the indiumphosphate family but also shows a new type of chain structure compared with those metalphosphates reported in the literature. Meanwhile, 2 and 3 present 2D undulated sheetlike structures with the same inorganic framework topology. The adjacent layers are stably packed together and exhibit interesting 3D supramolecular arrays with π−π interactions of the bipy groups. It is noteworthy that the different ratios of In:P for reactant addition lead to the formation of different structures in the presence of the same bipy ligands (In:P = 1:6 for compound 1 and In:P =1:4 for 2). By comparatively studying the photoluminescence properties of these compounds, we may conclude that the photoluminescence originates from ligand-centered π−π* transitions. The as-synthesized products are further characterized by powder X-ray diffraction, thermogravimetric analysis, 31P MAS NMR and IR spectroscopy, ICP, and elemental analysis.

Syntheses, crystal structures and photoluminescence properties of three novel organically bonded indium selenates or selenites

“…1, the asymmetric unit of 1 contains forty-five independent nonhydrogen atoms, nineteen of which belong to the inorganic framework (two In atoms, three Se atoms, twelve O atoms and two aqua ligands), twenty-four to two 2,2 0 -bipyridine (four N atoms and twenty C atoms) and the remains two for two lattice water molecules. Both indium(III) ions are octahedrally coordinated by a bidentate chelating 2,2 0 -bipyridine ligand, three SeO (Table 2), which are comparable to the reported indium compounds [25,26]. Hence, the indium octahedron in compound 1 is slightly distorted.…”

“…Compound 2 shows an emission band at l max ¼ 389 nm under 357 nm excitation whereas compound 3 exhibits an emission band at l max ¼ 389 nm under 350 nm excitation. The emission bands of 1, 2 and 3 can be attributed to the intra-ligand luminescence [25].…”

Solvothermal syntheses and structures of indium(III)-binaphthalenyl dicarboxylate complexes with yellow/blue luminescence

“…The choice of metal ions is also important. The research results from our and some other groups indicate that In(III) is a good candidate for the construction of MOFs [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. In contrast to the four-or six-coordinated fashions of divalent transition metal ions, In(III) ions have the ability to adopt MO 6 [23,25], MO 7 [23][24][25], or even MO 8 [26] coordination modes, which can benefit to the diversity of MOF framework, while the increased valence charge of In(III) may also show some influence on the resulting structures.…”

(2,2′-bipy)[In2(OH)2(H2O)](SO4)2: The first indium sulfate with a layer structure

“…The fluorescent emission band of the title compound is redshifted relative to the ligand, which may be due to perturbation of the p*-p transition of the 2,2 0 -bipy ligand by the metal atom. We may conclude that the fluorescent emission of the title compound originates from ligandcentered p*-p transitions [32,33].…”

“…To date, using this approach, a rich structural chemistry has already been established in metal phosphates [43,44]. In these materials, using 2,2 0 -bipy as the organic ligand, two indium phosphates, In 3 F 2 (2,2 0 -bipy) 2 (HPO 4 ) 2 (H 1.5 PO 4 ) 2 and In 2 F 2 (H 2 O)(2,2 0 -bipy)(HPO 4 ) 2 have been reported and they exhibit novel framework structures [32]. In 3 F 2 (2,2 0 -bipy) 2 (HPO 4 ) 2 (H 1.5 PO 4 ) 2 has a 1D neutral chain structure which is built up by the heptamer units, In 2 F 2 (H 2 O)(2,2 0 -bipy)(HPO 4 ) 2 possesses a 2D layer structure which consists of a corner-sharingcorner chain and an edge-sharing In 2 O 6 F 4 dimer.…”