Frameworks by Solvent‐Free Synthesis of Rare Earth Chlorides with Molten 1,3‐Benzodinitrile and Tailoring of the Particle Size: _∞³[LnCl₃{1,3‐C₆H₄(CN)₂}], Ln = Y, Dy, Ho, Er, Yb

Abstract

The solvent‐free melt reactions of anhydrous rare earth trichlorides with molten 1,3‐benzodinitrile [1,3‐C6H4(CN)2, C8H4N2] result in isophthalonitrile frameworks of the rare earth elements. The particle size of the products can bevaried from the millimeter to the nanometer scale (down to 50–400 nm) depending on the synthesis conditions. Thus, these network structures are among the very few coordination polymers that can be synthesized as nanoparticles. A constitution of 1:1 concerning LnCl3/1,3‐C6H4(CN)2 is found for Y (1), Dy (2), Ho (3), Er (4), and Yb (5) in isotypic∞3[LnCl3{1,3‐C6H4(CN)2}]. The ligand 1,3‐C6H4(CN)2 functions both as chemical scissors and replaces chloride linkages by degrading the rare earth chloride structures, and subsequently forms new 3D‐framework structures. They consist of strands of chlorido‐coordinated lanthanide atoms, which are linked in two dimensions by 1,3‐C6H4(CN)2 molecules. Compounds 1–5 were obtained as single crystals from the melt reaction, and their crystal structures were determined by single‐crystal X‐ray analysis. They can also be obtained as nanocrystalline materials from a ball mill treatment, identified by electron microscopy (REM) and EDX analysis.

Enhancing luminescence properties of lanthanide(iii)/pyrimidine-4,6-dicarboxylato system by solvent-free approach

“…16 One of the main conclusions derived from the few examples reported to date is that the use of organic reactants and/or hydrated metal salts with a low melting point is advantageous to obtain well crystalline compounds. 1a Particularly for lanthanide-organic polymers, most of the compounds obtained through this route involve reactions with melts of the ligands 9,17 or the use of a second element or solvent in order to activate the metal. 18 However, the use of ligands with high melting points, such as pmdc (m.p.…”

“…8 Furthermore, coordination polymers formed through this method tend to have a higher connectivity, in case the ligand shows an appropriate coordinative ability. 9 Although most of the compounds prepared by solvent-free synthesis are non-porous, few examples of porous ones have been recently published. 10 In this sense, pyrimidine-4,6-dicarboxylic acid (H 2 pmdc) has demonstrated a remarkable capacity in coordination chemistry due to its large number of donor atoms according to such a small molecule, providing porous and non-porous CPs.…”

Polymorphism of isotypic series of homoleptic 1,2,3-triazolate MOFs [Ln(Tz*)3] containing the heavy lanthanides Gd–Lu: from open to dense frameworks of varying dimensionality

“…Thus, we were able to obtain a wide range of Ln-NMOFs by utilizing rare earth metals and aromatic N-heterocycles [15][16][17][18][19]. For linker ligands that cannot be used in redox reactions metal halides together with melts of N-donor ligands were successfully applied recently [20][21][22][23][24]. 1H-1,2,3-triazole proved a suitable linker for Ln--N--MOFs, as reactions with europium and terbium resulted in the mixed valent MOF 3 1 [Eu 3 (Tz * ) 6 (Tz * H) 2 ] [25], (Tz*) -¼ 1,2,3-triazolate anion, C 2 H 2 N 3 -, Tz*H ¼ 1H-1,2,3-triazole, C 2 H 3 N 3 , and the trivalent 2 1 [Tb(Tz*) 3 ] [26].…”

Luminescent coordination polymers for the VIS and NIR range constituting LnCl3 and 1,2-bis(4-pyridyl)ethane

“…21 The Ln-N distances are also in the reported range. 23,25,26 They match with the lanthanide contraction, beginning with the shortest distance for Yb-N (2.473(3)-2.509(3) pm, followed by Dy-N (2.522(3)-2.571(4) pm), and Ce-N (2.653(2)-2.693(2) pm). The crystal structure analysis reveals a layered 2D structure with a honeycomb-like topology interconnected by bpe molecules to a 3D structure with dia topology (Fig.…”