Direct Synthesis and Mass Spectroscopic Observation of the {M₄₀} Polyoxothiometalate Wheel

Abstract

The nanosized, 2.2 nm, {Mo 40 24-wheel, 1a, was characterised by single-crystal X-ray diffraction analysis, IR, Raman, UV/Vis and flame atomic absorption spectroscopy (FAAS). Solid state and solution Raman spectroscopic studies allowed the unambiguous determination of the critical conditions by which compound 1 retains its integrity in solution.

The solution chemistry and reactivity of lacunary Keggin silicotungstates monitored in real-time by a combination of mass spectrometry and electrochemistry

“…24 However, this approach may not be applicable to all POM systems, in particular for those of high nucleicity that are vulnerable to such a cationexchange process. 25,26 Bonchio et al 15 Considering that the structural integrity of a lacunary complex is pH dependent, the solution stability of 1, 2 and 3 upon standing time was examined while keeping the respective pH values constant (6.4 for 1, 6.9 for 2 and 8.9 for 3) (Fig. S1 (ESI †)).…”

Use of ion-mobility mass spectrometry (IMS-MS) to map polyoxometalate Keplerate clusters and their supramolecular assemblies

“…It has also been used to study POM self-assembly mechanisms, 5,6 and as a discovery tool to detect new structures present in reaction mixtures prior to isolation. [7][8][9] Unfortunately, deconvolution of these systems can be difficult: use of a narrow range of building blocks, often in vast numbers, yields multiple species of very similar mass-to-charge ratios (m/z), but very different sizes/structures, resulting in overlapping envelopes in the mass spectra. 10 Ion mobility mass spectrometry (IMS-MS) is promising as a means to resolve this plethora of isobaric ions, separating according to their size/shape along with m/z.…”

Synthesis, Structural and Physicochemical Characterization of a Titanium(IV) Compound with the Hydroxamate Ligand N,2-Dihydroxybenzamide

“…(a) 698.98, 736.93, and 768.95 m / z with the formulae of {Ti III 2 O 2 (OCH 3 ) 3 (C 7 H 5 NO 3 ) 3 (OH 2 )H 6 } – , {Ti III 2 O 2 (C 7 H 5 NO 3 ) 4 H 5 } – and {Ti III 2 O 2 (OCH 3 ) (C 7 H 5 NO 3 ) 4 H 6 } – for the dinuclear fragment and at (b) 895.911 and 931.90 m / z with the formulae of {Ti III 3 O 2 (OCH 3 )(C 7 H 5 NO 3 ) 4 (HOCH 3 ) 2 (OH 2 )H 3 } – and {Ti III 3 O 2 (OCH 3 )(C 7 H 5 NO 3 ) 4 (HOCH 3 ) 2 (OH 2 ) 3 H 3 } – for the trinuclear fragments, respectively. The observation of different oxidation states for the metal centers and the presence of other fragments during the studies is due to the ionization and transfer process and has been observed in numerous occasions [ 53 , 54 , 55 , 56 , 57 ].…”

“…(a) 698.98, 736.93, and 768.95 m/z with the formulae of {Ti III 2O2(OCH3)3(C7H5NO3)3(OH2)H6} -, {Ti III 2O2(C7H5NO3)4H5} -and {Ti III 2O2(OCH3) (C7H5NO3)4H6} -for the dinuclear fragment and at (b) 895.911 and 931.90 m/z with the formulae of {Ti III 3O2(OCH3)(C7H5NO3)4(HOCH3)2(OH2)H3} -and {Ti III 3O2(OCH3)(C7H5NO3)4(HOCH3)2(OH2)3H3} -for the trinuclear fragments, respectively. The observation of different oxidation states for the metal centers and the presence of other fragments during the studies is due to the ionization and transfer process and has been observed in numerous occasions [53][54][55][56][57]. The high m/z region of the negative ion mass spectrum of 1 (Figure 4) exhibits characteristic isotopic distribution patterns which can be attributed to the tetranuclear cluster containing the inorganic core {Ti 4 O 2 } and are centered in the region ca.…”

“…III 3 O 2 (OCH 3 )(C 7 H 5 NO 3 ) 4 (HOCH 3 ) 2 (OH 2 ) 3 H 3 }for the trinuclear fragments, respectively. The observation of different oxidation states for the metal centers and the presence of other fragments during the studies is due to the ionization and transfer process and has been observed in numerous occasions [53][54][55][56][57].…”