6 research outputs found
Syntheses, Structures, Luminescence, and Magnetic Properties of a Series of Novel Coordination Polymers Constructed by Nanosized [Ln<sub>8</sub>Fe<sub>4</sub>] Rings
A total
of five three-dimensional Ln-Fe coordination polymers (CPs)
[(CH<sub>3</sub>)<sub>2</sub>NH]Ā[(CH<sub>3</sub>)<sub>2</sub>NH<sub>2</sub>]Ā[Ln<sub>2</sub>FeĀ(SO<sub>4</sub>)<sub>4</sub>(L)]ĀĀ·3H<sub>2</sub>O (Ln = Eu, <b>1</b>; Dy, <b>2</b>; Gd, <b>3</b>; Sm, <b>4</b>; Er, <b>5</b>; H<sub>2</sub>L = tartaric acid) have been successfully synthesized
under solvothermal conditions and characterized by infrared spectroscopy,
thermogravimetric analysis, elemental analyses, luminescence, and
magnetic properties. Structural analysis indicates that the frameworks
of <b>1</b>ā<b>5</b> are constructed from novel
[Ln<sub>8</sub>Fe<sub>4</sub>] rings. In the strcutures of <b>1</b>ā<b>5</b>, Ln<sup>III</sup> and Fe<sup>III</sup> ions
interconnect through O donors of sulfate anions to generate a one-dimensional
chain, and the adjacent chains are joined together by ligand [L]<sup>2ā</sup> to form a two-dimensional zonary plane, which is
further bridged by ligand [L]<sup>2ā</sup> to give a new topology
and named as ā<i><b>Xhd</b></i><b>1</b>ā. Magnetic properties of <b>2</b> and <b>3</b> were investigated using variable temperature magnetic susceptibility,
and weak ferromagnetic exchange between the Fe<sup>III</sup> and Ln<sup>III</sup> ions has been established for the Gd derivative. Meanwhile,
we also studied luminescence spectra and luminescence lifetimes of <b>1</b> and <b>4</b> in the solid state at room temperature.
The luminescence lifetime of <b>1</b> is 0.98 ms, which is significantly
longer than the values in the reported Eu<sup>3+</sup> coordination
polymers
Chiral [Mo<sub>8</sub>O<sub>26</sub>]<sup>4ā</sup> Polyoxoanion-Induced Three-Dimensional Architectures With Homochiral Eight-Fold Interpenetrated MetalāOrganic Frameworks
A pair
of novel chiral compounds based on homochiral 8-fold interpenetrated
metalāorganic frameworks (MOFs) and chiral polyoxometalates
(POMs), formulated as d-[CuĀ(4,4ā²-bipy)<sub>1.5</sub>]<sub>4</sub>Ā[Mo<sub>8</sub>O<sub>26</sub>] (d-<b>1</b>) and l-[CuĀ(4,4ā²-bipy)<sub>1.5</sub>]<sub>4</sub>Ā[Mo<sub>8</sub>O<sub>26</sub>] (l-<b>1</b>) (4,4ā²-bipy = 4,4ā²-bipyridine), have been successfully
synthesized and characterized by single crystal X-ray diffraction,
infrared, thermogravimetric analysis, elemental analysis, and solid
circular dichroism spectra. Structural analysis indicates that two
compounds are enantiomers. The connection of copper cations and 4,4ā²-bipy
ligands generates helical infinite chains, while adjacent chains are
further linked by CuāN bonds to form a three-dimensional interpenetrating
framework with a (10,3)-a topology. Interestingly, the chiral [Mo<sub>8</sub>O<sub>26</sub>]<sup>4ā</sup> polyanions are encapsulated
in the chiral MOFs via sharing the oxygen atoms. Both d-
and l-[CuĀ(4,4ā²-bipy)<sub>1.5</sub>]<sub>4</sub>Ā[Mo<sub>8</sub>O<sub>26</sub>] crystallize in chiral space group <i>C</i>222<sub>1</sub>. Additionally, two compounds represent
new examples of chiral self-assembly
An Unprecedented MāO Cluster Constructed from Nanosized {[C<sub>5</sub>NH<sub>5</sub>]<sub>9</sub>[H<sub>31</sub>Mo<sup>V</sup><sub>12</sub>O<sub>24</sub>Co<sup>II</sup><sub>12</sub>(PO<sub>4</sub>)<sub>23</sub>(H<sub>2</sub>O)<sub>4</sub>]}<sup>2ā</sup> Anions Exhibiting Interesting Nonlinear-Optical Properties
A novel high-nuclear
nanosized cluster modified by conjugated organic ligands (pyridine
and imidazole), [C<sub>5</sub>NH<sub>5</sub>]<sub>8</sub>Ā[C<sub>3</sub>H<sub>5</sub>N<sub>2</sub>]<sub>2</sub>Ā{[C<sub>5</sub>NH<sub>5</sub>]<sub>9</sub>āĀ[H<sub>31</sub>Mo<sub>12</sub>O<sub>24</sub>Co<sub>12</sub>āĀ(PO<sub>4</sub>)<sub>23</sub>Ā(H<sub>2</sub>O)<sub>4</sub>]}Ā·12H<sub>2</sub>O (<b>1</b>), has been successfully isolated under hydrothermal conditions
and structurally characterized. Compound <b>1</b> consists of
12 Co<sup>II</sup> and 12 Mo<sup>V</sup> ions linked by 23 {PO<sub>4</sub>} groups, exhibiting unprecedented nanosized ship-shaped clusters.
The magnetic measurements reveal that compound <b>1</b> exhibits
dominant antiferromagnetic interactions. Additionally, pyridine and
imidazole ligands enhance the delocalized electron effects of clusters,
and the third-order nonlinear-optical response of compound <b>1</b> is excellent
l- and dā[LnZn(IN)<sub>3</sub>(C<sub>2</sub>H<sub>4</sub>O<sub>2</sub>)]<sub><i>n</i></sub> (Ln = Eu, Sm, and Gd): Chiral Enantiomerically 3D 3dā4f Coordination Polymers Constructed by Interesting Butterfly-like Building Units and ā[Ln-O-Zn]<sub><i>n</i></sub>ā Helices
A total
of six three-dimensional chiral coordination compounds l-
and d-[LnZnĀ(IN)<sub>3</sub>Ā(C<sub>2</sub>H<sub>4</sub>O<sub>2</sub>)]<sub><i>n</i></sub> (Ln = Eu, Sm, and Gd;
HIN = isonicotinic acid) have been successfully synthesized under
hydrothermal conditions without any chiral auxiliary and characterized
by IR, TG, elemental analyses, and solid-state circular dichroism
spectra. The structures of <b>1</b>ā<b>6</b> were determined
by single-crystal X-ray structural analysis, which shows that l-[LnZnĀ(IN)<sub>3</sub>Ā(C<sub>2</sub>H<sub>4</sub>O<sub>2</sub>)]<i><sub>n</sub></i> (Ln = Eu (<b>1</b>),
Sm (<b>2</b>), and Gd (<b>3</b>)) crystallize in space
group <i>P</i>6<sub>5</sub>22 and are levogyrate. The chiral frameworks of l-[LnZnĀ(IN)<sub>3</sub>(C<sub>2</sub>H<sub>4</sub>O<sub>2</sub>)]<sub><i>n</i></sub> are constructed from l-helical
Ln-O-Zn cluster chains, while adjacent l-type helical ā[Ln-O-Zn]<sub><i>n</i></sub>ā chains are connected through IN<sup>ā</sup> ligands. d-[LnZnĀ(IN)<sub>3</sub>Ā(C<sub>2</sub>H<sub>4</sub>O<sub>2</sub>)]<sub><i>n</i></sub> (Ln
= Eu (<b>4</b>), Sm (<b>5</b>), and Gd (<b>6</b>)) crystallize in space group <i>P</i>6<sub>1</sub>22,
and their chiral frameworks consist of d-helical Ln-O-Zn
cluster chains. The observed second-harmonic generation efficiencies
of [EuZnĀ(IN)<sub>3</sub>Ā(C<sub>2</sub>H<sub>4</sub>O<sub>2</sub>)]<sub><i>n</i></sub>, [SmZnĀ(IN)<sub>3</sub>Ā(C<sub>2</sub>H<sub>4</sub>O<sub>2</sub>)]<sub><i>n</i></sub>,
and [GdZnĀ(IN)<sub>3</sub>Ā(C<sub>2</sub>H<sub>4</sub>O<sub>2</sub>)]<sub><i>n</i></sub> are 0.4, 0.3, and 0.3 times that
of urea, respectively. We also studied luminescence spectra and luminescence
lifetimes of <b>1</b> and <b>2</b>. The luminescence lifetimes
of <b>1</b> and <b>2</b> are 1.18 ms, and 29.6 Ī¼s,
respectively
POM Constructed from Super-Sodalite Cage with Extra-Large 24-Membered Channels: Effective Sorbent for Uranium Adsorption
A POMs-based
sorbent functionalized by phosphate groups: H<sub>33</sub>Na<sub>14</sub>Mo<sup>V</sup><sub>24</sub>Mo<sup>VI</sup><sub>2</sub>(PO<sub>4</sub>)<sub>11</sub>O<sub>73</sub> has been
successfully isolated under hydrothermal conditions. The cooperative
assembly of the ring-shaped polyoxometalate structural building unit
{P<sub>4</sub>Mo<sub>6</sub>} and MoO<sub>4</sub> tetrahedra linkers
gives rise to an unprecedented supersodalite cage containing approximately
spherical cavities with a 8.76 Ć
diameter. As POMs-based inorganic
material, compound <b>1</b> was first applied as sorbent to
adsorb UĀ(VI) from aqueous solution, exhibiting good stability, high
efficiency, and selectivity. The maximum sorption capacity reaches
325.9 mg g<sup>ā1</sup>, which may capture radionuclides through
cooperative binding of the phosphate groups. The adsorbed UĀ(VI) could
be nearly drastically eluted when using 0.1 M Na<sub>2</sub>CO<sub>3</sub> and the sorption capacity for UĀ(VI) slightly decreased 10.16%
through five successive sorption/desorption cycles. This work represents
first application of POMs-based inorganic materials as sorbent to
adsorb uranium from aqueous solution and provides a feasible approach
for the entrapment and recovery of radionuclides
POM Constructed from Super-Sodalite Cage with Extra-Large 24-Membered Channels: Effective Sorbent for Uranium Adsorption
A POMs-based
sorbent functionalized by phosphate groups: H<sub>33</sub>Na<sub>14</sub>Mo<sup>V</sup><sub>24</sub>Mo<sup>VI</sup><sub>2</sub>(PO<sub>4</sub>)<sub>11</sub>O<sub>73</sub> has been
successfully isolated under hydrothermal conditions. The cooperative
assembly of the ring-shaped polyoxometalate structural building unit
{P<sub>4</sub>Mo<sub>6</sub>} and MoO<sub>4</sub> tetrahedra linkers
gives rise to an unprecedented supersodalite cage containing approximately
spherical cavities with a 8.76 Ć
diameter. As POMs-based inorganic
material, compound <b>1</b> was first applied as sorbent to
adsorb UĀ(VI) from aqueous solution, exhibiting good stability, high
efficiency, and selectivity. The maximum sorption capacity reaches
325.9 mg g<sup>ā1</sup>, which may capture radionuclides through
cooperative binding of the phosphate groups. The adsorbed UĀ(VI) could
be nearly drastically eluted when using 0.1 M Na<sub>2</sub>CO<sub>3</sub> and the sorption capacity for UĀ(VI) slightly decreased 10.16%
through five successive sorption/desorption cycles. This work represents
first application of POMs-based inorganic materials as sorbent to
adsorb uranium from aqueous solution and provides a feasible approach
for the entrapment and recovery of radionuclides