Syntheses, Crystal Structures, and Magnetic Properties of [Ln^III₂(Succinate)₃(H₂O)₂]·0.5H₂O [Ln = Pr, Nd, Sm, Eu, Gd, and Dy] Polymeric Networks:  Unusual Ferromagnetic Coupling in Gd Derivative

Abstract

Lanthanide-organic coordination polymeric networks of [Ln(III)2(suc)3(H2O)2].0.5H2O [suc = succinate dianion, Ln = Pr (1), Nd (2), Sm (3), Eu (4), Gd (5), and Dy (6)] have been synthesized and characterized by single-crystal X-ray diffraction analyses. The structural determination reveals that complexes are isomorphous, all crystallizing in monoclinic system, space group I2/a(.) The complexes possess a 3D architecture with Ln ion in a nine-coordination geometry attained by eight oxygen atoms from succinate and one oxygen atom from an aqua ligand. Low-temperature magnetic study indicates that ferromagnetic interaction is present in case of Gd(III) and Dy(III). Antiferromagnetic interaction is observed for the rest of the complexes. Density functional theory calculations are performed which support the existence of a superexchange ferromagnetic coupling in Gd(III) ions, whereas classical crystal field model has been applied to study the complexes 1, 2, 3, and 6.

The Construction of Open GdIII Metal–Organic Frameworks Based on Methanetriacetic Acid: New Objects with an Old Ligand

“…[25] The magnetic behaviour of compounds 2 and 3 follows this prediction. This agreement is also observed when looking at the previous cases in which the m-O(1);k 2 O(1),O(2)/double syn-syn carboxylato (2) [26] or the m-O(1);k 2 O(1),O(2)/single syn-syn carboxylato (3) [27] bridge occur.…”

Elaboration of Luminescent and Magnetic Hybrid Networks Based on Lanthanide Ions and Imidazolium Dicarboxylate Salts: Influence of the Synthesis Conditions

“…Figure 14b is similar. The χT product decreases from 1.37 emu·K·mol −1 at 300 K to 0.58 emu·K·mol −1 at 1.8 K. Such behavior is commonly encountered for the isolated Nd 3+ ion [33,[47][48][49]. The values of the χT products at 300 K are close to that expected for the free Nd 3+ ion (1.64 emu•K•mol −1 for gJ = 8/11).…”

“…In the case of the samarium nitrate (see Figure 15), one structure [Sm(L)(ox)(H2O)]•H2O is obtained when oxalic acid is added to the reaction medium whatever the nature of the imidazolium ligand (i.e., zwitterionic [HL] Such behavior is commonly encountered for the isolated Nd 3+ ion [33,[47][48][49]. The values of the χT products at 300 K are close to that expected for the free Nd 3+ ion (1.64 emu·K·mol −1 for g J = 8/11).…”

Reversible Breaking and Forming of Metal–Ligand Coordination Bonds: Temperature‐Triggered Single‐Crystal to Single‐Crystal Transformation in a Metal–Organic Framework

“…Rare-earth succinates have been studied widely and several inorganic-organic frameworks have been obtained and characterized. [3,[7][8][9][10][11][12][13][14] Although the properties of the rare-earth element and the flexible succinate anion are combined in these frameworks, the properties of the compounds such as luminescence [8,14,15] or catalysis [3] have been evaluated in only a few studies. However, the transformations of one hybrid polymeric structure to another are rare in solid-state supramolecular reactions as the breaking and formation of bonds should occur in more than one direction simultaneously.…”