Reversible dimerization of decaniobate

Lewis Base Catalytic Properties of [Nb10O28]6− for CO2 Fixation to Epoxide: Kinetic and Theoretical Studies

“…[27] The experimentally observed IR spectrum ( Figure S4) agreed well with one that was previously reported. [26] Contentso fC(41.08 wt %), H (7.70 wt %) and N( 2.97 wt %) in the sample determined experimentally agree well with those calculated forC 96 H 216 N 6 Nb 10 O 28 : C( 40.72 wt %);H(7.69 wt %);a nd N( 2.97 wt %). These results indicatet he successful formationo ft he decaniobate structure in the prepared sample of (TBA) 6 [Nb 10 O 28 ].…”

“…(TBA) 6 [Nb 10 O 28 ]w as synthesized according to the procedure in the literature with slight modifications. [26] The product was characterized by negative-ion electrospray ionization mass spectrometry (ESI-MS), Nb K-edge X-ray absorption fine-structure (XAFS) spectroscopy,i nfrared (IR) spectroscopy,a nd elemental analysis.E SI-MS showed as eries of mass peaks assigned to monovalent anions( TBA) x [H 5Àx Nb 10 O 28 ] À (x = 3-5) generated by partial protonation to [Nb 10 O 28 ] 6À during the ESI process ( Figure S1, Table S1). The geometric structure was studied by Nb K-edge XAFS analysis.…”

“…We chose the tetrabutylammonium (TBA) salt of a decaniobate cluster, (TBA) 6 [Nb 10 O 28 ], as a catalyst because of its high dispersibility in organic solvents including styrene oxide. (TBA) 6 [Nb 10 O 28 ] was synthesized according to the procedure in the literature with slight modifications . The product was characterized by negative‐ion electrospray ionization mass spectrometry (ESI‐MS), Nb K‐edge X‐ray absorption fine‐structure (XAFS) spectroscopy, infrared (IR) spectroscopy, and elemental analysis.…”

Microwave Synthesis of Alkali‐Free Hexaniobate, Decaniobate, and Hexatantalate Polyoxometalate Ions

“…It has, to the best of our knowledge, not been made directly from niobic acid, which would require an Nb/OH – ratio of 2.5. Instead, it has been made through reaction of acid precipitated Nb 6 redissolved in organic solvent and heated, or by acidification of aqueous solutions of Nb 10 . Similarly, whereas Ta 10 is known, it has not been prepared from tantalic acid, but – analogously to [Nb 20 O 54 ] 8– – is made by redissolving acid‐precipitated [Ta 6 O 19 ] 8– in organic solvent.…”

Which is the most basic oxygen in [Ta6O19]8−? — Synthesis and structural characterization of [H2Ta6O19]6−

“…We have been studying the chemistry of polyniobates and polytantalates in non-aqueous media [33,34] [35].…”