Rui Pan

A Series of Aluminoborates Templated or Supported by Zinc-Amine Complexes.

A series of open-framework aluminoborates (ABOs), namely, [Zn2 (en)5 ][Al2 B10 O20 ] (1), [Zn(en)(dien)][AlB5 O10 ] (2), [Zn(en)3 ][AlB7 O12 (OH)2 ] (3), [Zn(en)2 ][AlB5 O10 ] (4), K7 {AlO0.5 [BO2 (OH)]Zn@[B12 O21 (OH)3 ]}⋅H2 O (5) (en=ethylenediamine, dien=diethylenetriamine) have been made under mild solvothermal conditions and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analysis, IR and UV/Vis spectroscopy, thermogravimetric analysis, and nonlinear optical determination. They were classified as two types: Compounds 1-4 contain intersecting channels and exhibit various 4-connected nets built by AlO4 tetrahedra and oxo boron clusters, zinc-amine complexes act as the templates (1-3) or directly bond to the walls of the ABO (4); compound 5 exhibits a double-layer structure made by nanosized [BO2 (OH)]Zn@[B12 O21 (OH)3 ] ({BZn@B12 }) clusters with Al2 O7 dimers, the channels are within the layer. The second harmonic generation (SHG) measurement shows that the SHG responses of 1-3 are about 2.5, 1.6, and 0.5 times that of KH2 PO4 . Compounds 1-2 are type I phase-matchable materials. UV/Vis spectroscopy indicates that compounds 1-5 are wide-band-gap semiconductors.

Diverse Ligand-Functionalized Mixed-Valent Hexamanganese Sandwiched Silicotungstates with Single-Molecule Magnet Behavior.

Under hydrothermal conditions, replacement of the water molecules in the [Mn(III) 4 Mn(II) 2 O4 (H2 O)4 ](8+) cluster of mixed-valent Mn6 sandwiched silicotungstate [(B-α-SiW9 O34 )2 Mn(III) 4 Mn(II) 2 O4 (H2 O)4 ](12-) (1 a) with organic N ligands led to the isolation of five organic-inorganic hybrid, Mn6 -substituted polyoxometalates (POMs) 2-6. They were all structurally characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, diffuse-reflectance spectroscopy, and powder and single-crystal X-ray diffraction. Compounds 2-6 represent the first series of mixed-valent {Mn(III) 4 Mn(II) 2 O4 (H2 O)4-n (L)n } sandwiched POMs covalently functionalized by organic ligands. The preparation of 1-6 not only indicates that the double-cubane {Mn(III) 4 Mn(II) 2 O4 (H2 O)4-n (L)n } clusters are very stable fragments in both conventional aqueous solution and hydrothermal systems and that organic functionalization of the [Mn(III) 4 Mn(II) 2 O4 (H2 O)4 ](8+) cluster by substitution reactions is feasible, but also demonstrates that hydrothermal environments can promote and facilitate the occurrence of this substitution reaction. This work confirms that hydrothermal synthesis is effective for making novel mixed-valent POMs substituted with transition-metal (TM) clusters by combining lacunary Keggin precursors with TM cations and tunable organic ligands. Furthermore, magnetic measurements reveal that 3 and 6 exhibit single-molecule magnet behavior.

Supramolecular nanotubes constructed from 3d–4f heterometallic sandwiched polyoxotungstate dimers

By the hydrothermal technique, a series of organic–inorganic hybrid polyoxometalates (POMs) Hx(H2en)y [Fe2Ln(β-PW10O37)2(Tart)]·nH2O (Ln = La3+, (x, y, n) = (5, 3, 9) for 1; Ln = Ce3+, (x, y, n) = (5, 3, 7) for 2; Ln = Sm3+, (x, y, n) = (3, 4, 25) for 3; Ln = Tb3+, (x, y, n) = (3, 4, 21) for 4; H2Tart = tartaric acid) have been obtained and structurally characterized by elemental analyses, IR spectroscopy, thermogravimetric analyses and single-crystal X-ray diffraction. The common structural characteristics of 1–4 consist of a [Fe2Ln(β-PW10O37)2(Tart)]9− unit, in which transition metal and lanthanide ions co-exist in the vacant site of divacant [β-PW10O37]9− with the assistance of Tart ligands. It should be pointed out that 1–4 represent the first 3d–4f heterometallic cluster sandwiched phosphotungstate dimers, [Fe2Ln(β-PW10O37)2(Tart)]9−, linked by Fe–O–Ln–O–Fe bonds. Furthermore, 3 and 4 exist as rare supramolecular nanotubes built from the organic–inorganic hybrid 3d–4f POM units. Also, the photochromism and optical properties of 1–4 have been studied.

CsBxGe6–xO12 (x = 1): A Zeolite Sodalite-Type Borogermanate with a High Ge/B Ratio by Partial Boron Substitution

The partial replacement of Ge atoms in tetrahedral positions by a small number of B atoms leads to a new microporous borogermanate, CsBxGe6-xO12 (x = 1), under solvothermal conditions. Its framework shows the highest atomic ratios of Ge/B in reported borogermanates and leads to a new type of zeolite sodalite-type net.