4f-Block Metal Complexes as Secondary Building Units in Preparing 4d–4f Coordination Polymers: Preparation, Structures, and Luminescent Properties of [Ln₂L₆(H₂O)₄]·{[Ln₂L₄(H₂O)₆](NO₃)₂} and {[AgLnL₂(H₂O)₃](NO₃)₂(H₂O)₄} (L = 3-Pyridinepropinoate, Ln = Eu, Tb, Nd)

Abstract

Three new 4d−4f metal−organic coordination polymers were prepared by using 4f-block metal complexes as secondary building units. Discrete 4f complexes, [Ln 2 L 6 (H 2 O) 4 ]•{[Ln 2 L 4 (H 2 O) 8 ](NO 3 ) 2 } {Ln = Eu (1), Tb (2), Nd (3)}, were prepared by microwave-heating a mixture of Ln(NO 3 ) 3 •nH 2 O, 3-pyridinepropionic acid (HL), and NaOH in water for 1 min. Compounds 1−3 were subsequently treated with AgNO 3 to form three-dimensional Ag−Ln coordination polymers, [AgLnL 2 (H 2 O) 3 ](NO 3 ) 2 (H 2 O) 4 {Ln = Eu (4), Tb ( 5), Nd (6)}. Compounds 1−3 are isostructural and consist of two dimers: a neural dimer and an ionic dimer. In these compounds, the pyridyl N atoms of ligands do not coordinate to the Ln 3+ ions. In isostructural coordination polymers 4−6, the pyridyl N atoms are bonded to soft Ag + ions, and carboxylate oxygen atoms are bonded to hard Ln 3+ ions. Compounds 1 and 4 exhibit practically the same red luminescence in the solid state, and compounds 2 and 5 exhibit the green luminescence, but compounds 3 and 6 do not exhibit photoluminescence in the visible region.

3-D Silver(I)—Lanthanide(III) Heterometallic-Organic Frameworks Constructed from 2,2′-Bipyridine-3,3′-dicarboxylic Acid: Synthesis, Structure, Photoluminescence, and Their Remarkable Thermostability

“…Some investigations have shown that Ag + ion (4d 10 ) having a special closed outer shell electron configuration can provide a way to achieve novel heterometallic complexes with beautiful architectures and improved luminescent properties of the resulting Ag–Ln heterometallic complexes. − A typical strategy to construct Ag–Ln heterometallic MOFs lies in selecting proper ligands containing both oxygen and nitrogen atoms, such as nicotinic acid, , isonicotinic acid, ,,, or pyrazine-2-carboxylate . As a consequence, so far several Ag–Ln compounds based on these kind of ligands have been reported with one-dimensional (1-D) , and two-dimensional (2-D) ,, structures; however three-dimensional (3-D) frameworks structures of Ag–Ln MOFs are rarely acquired successfully, − probably due to the low coordination number of Ag + and the ligands used having low chelating positions. Therefore searching for multifunctional ligands possessing more coordinating sites still remains a challenge to construct 3-D Ag–Ln MOFs.…”

A Silver–Organic Frameworks Based on Flexible-Aromatic Dicarboxylate and Bipyridinyl Skeletons Coligand: Crystal Structure and Luminescence Property

“…Herein, we describe self-assembly of the flexible nitrogen-heterocyclic acid (such as ddpp) with pyridine as the kind of organic ligand with introduction an extended p-conjugated system [13]. Meanwhile, bipy has been proved to be a good candidate for pillar ligand due to its' strong coordination tendency to generate 1D to 3D moderately robust networks [14][15][16][17][18][19][20], exhibiting strong luminescences [21][22][23]. In this contribution, ddpp was employed as main ligand, and bipyridinyl skeletons as auxiliary ligand to obtain [(ddpp)Ag(bipy)] successfully via hydrosolvothermal reaction approach.…”

A Manganese Coordination Polymer and a Palladium Molecular Compound of 3-Pyridinepropionic acid (HL): [MnL2(H2O)2]∞and trans-[Pd(HL)2Cl2]

“…50 In addition, Zheng and co-workers prepared 3d− 4f polynuclear metal clusters under microwave-heating conditions. 54 We also reported on the microwave-assisted preparation of Ag-4f 42 and lanthanide (4f ) 43,49 coordination polymers.…”

“…Since 2010, our group has prepared a couple of pyridyl-carboxylate-type asymmetric linking ligands (L1-L6 in Chart 1) and their coordination polymers. [41][42][43][44][45][46][47][48] Coordination polymers are commonly prepared by various heating methods such as hydrothermal, hydro(solvo)thermal, solvothermal, and reflux methods, which typically require long reaction times. To overcome such vigorous conditions, microwave was recently employed to quickly bring about high heating effects.…”