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Two organic–inorganic composite vanadoborates Na2(Hen)4[B18V12O60]·16H2O (1) (en = ethylenediamine) and (H2en)6[B18V12O60]2·2tepa·11H2O (2) (tepa = tetraethylenepentamine) have been hydrothermally synthesized and characterized by elemental analyses, inductively coupled plasma atomic emission spectrometry (ICP-AES) analyses, IR spectra, and X-ray crystallography. Single-crystal structural analyses show that1exhibits a 2-D polyoxovanadium borate sheet architecture with a four-connected topology established by [B18V12O60]6−units via Na+bridges whereas the molecular unit of2consists of two discrete [B18V12O60]6−clusters, six diprotonated [H2en]2+cations, two tepa molecules, and 11 lattice water molecules. [ABSTRACT FROM AUTHOR]

[Me2NH2]2Na11 [X2W21NaO72(OH)2] ·34H2O (X: SbIII (I), BiIII (II)) are prepared by a one-pot self-assembly of aqueous solutions of Na2WO4, NaOAc, and Me2NH2Cl to which a HCl solution of SbCl3 (or Bi(NO3)3 and Zr(NO3)4 for (II)) is added dropwise. [ABSTRACT FROM AUTHOR]

Single crystals of Na13H7 [Ce(SeW17O59)2]·31H2O are prepared by reaction of Na2WO4 and Na2SeO3 with (NH4)2Ce(NO3)6 in an aqueous KCl-containing solution at pH 2 (stirring, 30 min; 17% yield). [ABSTRACT FROM AUTHOR]

Three lanthanide (Ln)-functionali z ed antimonotungstate (AT) clusters with a {Sb 4 O 4 Ln 3 (H 2 O) 8 } core [H 2 N(CH 3 ) 2 ] 14 Na 8 H 16 [Sb 4 O 4 Ln 3 (H 2 O) 8 W 2 O 4 (H 2 O) 2 ( B-α- SbW 9 O 33 ) 4 ] 2 ·87H 2 O [Ln = Dy 3+ ( 1 ), Ho 3+ ( 2 ), Y 3+ ( 3 )] were synthesized in an acidic aqueous solution. Their molecular structural unit comprises two {Sb 4 O 4 Ln 3 (H 2 O) 8 }-core-incorporated tetrameric [Sb 4 O 4 Ln 3 (H 2 O) 8 W 2 O 4 (H 2 O) 2 ( B-α- SbW 9 O 33 ) 4 ] 19- polyanionic units, each of which is assembled from an unprecedented [Sb 4 O 4 Ln 3 (H 2 O) 8 W 2 O 4 (H 2 O) 2 ] 17+ heteroatom cluster surrounded by four trivacant [ B-α- SbW 9 O 33 ] 9- subunits. What is noteworthy is that a tetrahedral {Sb 4 O 4 } cluster is located at the center of the polyanionic unit, as far as we know, which is very infrequent in multi-Ln-functionalized polyoxometalate chemistry. Solid-state luminescent properties and energy migration of AT ligands to Dy 3+ and Ho 3+ cations in 1 and 2 have been intensively probed at ambient temperature. By varying the exciting wavelength from 250 to 450 nm, the emitting color could vary from blue to yellow for 1 and blue to green-yellow for 2 , separately. In addition, high catalytic activities and good reusability of 2 as a heterogeneous catalyst for oxygenation reaction of sulfides have been systematically performed.

Two unique nanosized Nd 3+ -substituted selenotungstates Na 9 K 8 {[W 3 Nd 2 (H 2 O) 3 (NO 3 )O 6 ](B-α-SeW 9 O 33 ) 2 (α-Se 2 W 14 O 52 )}·35H 2 O (1) and [H 2 N(CH 3 ) 2 ] 7 H 9 Na 4 {[W 2 Nd 2 (H 2 O) 8 O 6 (OH) 2 (β-Se 2 W 14 O 52 )][W 3 Nd 2 (H 2 O) 6 O 7 (B-α-SeW 9 O 33 ) 2 ] 2 }·84H 2 O (2) were prepared by reacting NaSeO 3 , Na 2 WO 4 ·2H 2 O with Nd(NO 3 ) 3 ·6H 2 O in aqueous solution by controlling different cations and pH values. 1 was synthesized at pH = 4.3 in the presence of KCl, whereas 2 was synthesized at pH = 3.0 in the presence of [H 2 N(CH 3 ) 2 ]·Cl. The most striking structural feature of 1 and 2 is the coexistence of vacant Keggin and Dawson segments in the polyoxoanion, which is extremely rare in the field of polyoxometalate chemistry. The trimeric polyoxoanion of 1 can be perceived as a fusion of one α-type tetravacant Dawson [α-Se 2 W 14 O 52 ] 14- unit and two trivacant Keggin [B-α-SeW 9 O 33 ] 8- segments sealing a trigonal bipyramid pentanuclear [W 3 Nd 2 (H 2 O) 3 (NO 3 )O 6 ] 11+ cluster, while the pentameric polyoxoanion of 2 can be described as one β-type tetravacant Dawson [β-Se 2 W 14 O 52 ] 14- fragment and four trivacant Keggin [B-α-SeW 9 O 33 ] 8- segments anchoring a saddle-shaped [W 8 Nd 6 (H 2 O) 20 O 20 (OH) 2 ] 24+ cluster. In addition, the measurements of catalytic oxidation of aromatic thioethers show that 2 as a catalyst possesses extremely outstanding catalytic performance under mild reaction conditions.