Lanthanide–tungstobismuthate clusters based on [BiW9O33]9− building units: synthesis, crystal structures, luminescent and magnetic properties

Abstract

The reaction of Na(12)[Bi(2)W(22)O(74)(OH)(2)]·44H(2)O, Na(9)[BiW(9)O(33)]·16H(2)O, lanthanide chloride and Na(2)CO(3) in aqueous solution at a pH value of about 7.0 resulted in the three unprecedented giant lanthanide-tungstobismuthate clusters Na(x)H(22-x)[(BiW(9)O(33))(4)(WO(3)){Bi(6)(μ(3)-O)(4)(μ(2)-OH)(3)}(Ln(3)(H(2)O)(6)CO(3))]·nH(2)O {Ln = Pr(3+) (1), Nd(3+) (2), La(3+) (3), x = 22 (1), 22 (2), 20 (3), n = 95 (1), 91 (2), 73 (3)}. These three complexes represent the first examples of lanthanide ions encapsulated in polyoxotungstobismuthates and the largest polytungstobismuthates so far. Furthermore, a [{Bi(6)(μ(3)-O)(4)(μ(2)-OH)(3)}](7+) polyoxo cation was incorporated into the structure of these compounds. All complexes are characterized by single-crystal X-ray diffraction, IR spectra, electronic spectroscopy, thermogravimetric and elemental analysis. Magnetic investigation revealed that the progressive depopulation of excited Stark sublevels of the lanthanide ions at low temperature and the weak antiferromagnetic interaction between the neighboring metal centres are responsible for the magnetic properties of 1 and 2. The original synthesis strategy in this work may open a gateway to assembly of large lanthanide-tungstobismuthates clusters and novel multifunctional solid materials in aqueous solution under mild conditions.

Construction of polyoxometalates from dynamic lacunary polyoxotungstate building blocks and lanthanide linkers

“…[5][6][7][8][9][10] In this research field, various synthetic strategies including one-pot synthesis, step-by-step methods and "3-D printing" techniques have been explored. [14][15][16][17][18][19][20][21][22][23][24][25][26] Firstly, {XW 9 O 33 } is highly vacant and can coordinate with multiple metal ions in various modes. Therefore, the construction of POM-based polynuclear clusters can be viewed as a successive coexisting, activating and assembling process occurring in a reaction system containing various POM building units and linkers.…”

“…The trivacant Keggin-type cluster {B-α-XW 9 O 33 } (X = As III , Sb III , Bi III , Se IV , Te IV ), containing the central distorted tetrahedral unit {XO 3 }, displays a great advantage in this field due to several features, as follows. [14][15][16][17][18][19][20][21][22][23][24][25][26] Firstly, {XW 9 O 33 } is highly vacant and can coordinate with multiple metal ions in various modes. Secondly, the central heteroatoms have a lone pair of electrons on the outside, which can help prevent lacunary POM species from being saturated at a certain pH value and can restrict the coordination abilities of the central heteroatoms to TM or Ln ions.…”

Three {Bi2W21} Tungstobismuthate Clusters Linked by Acetate‐Stabilized Ln Bridges

“…Temperature dependence of the magnetic susceptibilities of 1 and 3 were carried out in the range of T = 300–1.8 K under an applied direct‐current (dc) field of 1000 Oe. As depicted in Figure a, the χ M of 1 exhibits a continuous rise from 0.011 emu mol –1 at 300 K to 0.097 emu mol –1 at 1.8 K. The χ M T of 1 at room temperature is 3.30 emu K mol –1 , in good accordance with the expected value for two non‐interacting Pr III ions ( S = 1, L = 5, 3 H 4 , g = 4/5) of 3.20 emu K mol –1 . This behaviour may be resulted from the split of the ninefold degenerate 3 H 4 ground state of Pr III ion by the crystal‐field effect into Stark levels.…”

A 3D all-inorganic architecture based on the [H2W12O42]10− building block with different alkaline-earth metal linkers: crystal structures, surface photovoltage and photoluminescent properties

“…10b,14 Therefore, it is certainly difficult to synthesize new polyoxometalates associated with alkaline-earth metal ions. In this work, by using a previous synthesis strategy, 15 alkaline-earth ions were introduced into the reaction system, and four 3D all-inorganic frameworks based on [H 2 W 12 O 42 ] 102 building units and alkaline-earth metal cations were successfully synthesized. The starting materials of the {Bi 2 W 22 O 74 (OH) 2 } precursor play an important role in the synthesis reaction, in which the [H 2 W 12 O 42 ] 102 anion was slowly re-assembled from the {Bi 2 W 22 O 74 (OH) 2 } precursor so as to avoid the formation of a precipitate.…”