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The reaction of [Ln(btfa)3(H2O)2] (btfa− = 4,4,4-trifluoro-1-phenyl-1,3-butanedionate) with additional 4,4,4-trifluoro-1-phenyl-1,3-butanedione (Hbtfa) and acridine (Acr) in ethanol allows the isolation of the mononuclear compounds HAcr[Nd(btfa)4]·EtOH, (1) and HAcr[Ln(btfa)4], Ln = Dy (2) and Yb (3); HAcr+ = acridinium cation. Magnetic measurements indicate that complexes 1–3 show field-induced single-ion magnet behavior with anisotropy energy barriers and preexponential factors of Ueff = 20.7 cm−1, τ0 = 24.5 × 10−8 s; Ueff = 40.5 cm−1, τ0 = 8.6 × 10−10 s and Ueff = 22.7 cm−1, τ0 = 8.4 × 10−8 s, for 1–3 respectively. The solid-state luminescence emission in the NIR region shows efficient energy transfer from the 4,4,4-trifluoro-1-phenyl-1,3-butanedionate ligands to the central Ln3+ ion in the case of compounds 1 and 3. [ABSTRACT FROM AUTHOR]

The crystal structure of the title compound, [YbCl2(H2O)6]Cl, was determined at 110 K. Samples were obtained from evaporated acetonitrile solutions containing the title compound, which consists of a [YbCl2(H2O)6]+ cation and a Cl− anion. The cations in the title compound sit on a twofold axis and form O—H...Cl hydrogen bonds with the nearby Cl− anion. The coordination geometry around the metal centre forms a distorted square antiprism. The ytterbium complex is isotypic with the europium complex [Tambrornino et al. (2014). Acta Cryst. E70, i27].

Two novel calix[4]arene macrocyclic ligands functionalized with four 1,3-diketone groups at the upper and hydroxyl ( 3 ) or propyloxy-groups ( 6 ) at the lower rims were synthesized and characterized using NMR, IR spectroscopy, mass spectrometry, and elemental analysis. UV–vis spectrophotometry and ESI mass spectrometry studies indicate 1:1 complex formation of ligands 3 and 6 with Ln(III) (Ln=Tb, Yb) in alkaline DMF solutions resulted from coordination of Ln(III) with 1,3-diketonate groups. Luminescence study of Ln(III) complexes with 3 and 6 reveals significant difference in antenna effects of their deprotonated forms on both Tb(III)- and Yb(III)-centered luminescence. Comparison of ligand-centered emission for ligands 3 and 6 points to the latter as more efficient antenna for Tb(III) and Yb(III). Different conformational behavior of ligands 3 and 6 in alkaline media is assumed as a reason for the experimentally observed difference in sensitization pathways in Ln(III) complexes with 3 and 6 . [ABSTRACT FROM AUTHOR]

• In situ Dimethylammonium by mild solvothermal. • In situ solvents generation can be tuned for preferred topologies. • Single crystal XRD and DFT computation. • Larger values of HOMO-LUMO energy gap is responsible for less reactive of complex. A new ytterbium(III) complex, (DMAH 2) 3 [Yb(Pydc) 3 ].4H 2 O (1) {Pydc = Pyridine-2,6-dicarboxylate anion, DMAH 2 = Dimethylammonium} has been prepared under mild solvothermal conditions and characterized by elemental analysis, IR spectroscopy, thermal analysis and single crystal X-ray diffraction. The DMAH 2 molecules in 1 , generated in situ from hydrolysis of N,N -dimethylformamide are responsible to assemble 2D coordination polymer through N-H···O and O-H···O hydrogen bonding. Magnetic susceptibility measurements indicate that the complex (1) obeys the Curie Weiss law and the overall magnetic behavior is typical for the presence of weak antiferromagnetic exchange coupling interactions. Theoretical data for geometrical parameters of complex 1 agree well with the experimental data. Large HOMO-LUMO energy gap of 4.33 eV has provided kinetic stability to the complex 1. NBO analysis reflects that intramolecular charge transfer occurred between ligand and metal orbitals with the highest stabilization energy of 1024.04 kcal/mol. The negative electrostatic potential at the nitrogen and dianionic pyridine-2,6-dicarboxylate regions confirms that these are dynamic locations for Yb(III) binding. : [Display omitted] [ABSTRACT FROM AUTHOR]

Synthesis, structure and properties of two alkali-lanthanide heterometallic coordination polymers with the stoichiometric formula [M(OH)(HO)Ln(NO)] (where M is Na and Ln, Er or Yb) are reported. They crystallize in the monoclinic P2/ c space group with very similar cell parameters: a = 15.8777(19) Å, b = 13.4173(18) Å, c = 13.3515(17) Å, β = 93.585(9)º, and V = 2838.8(6) Å for Er(III) and a = 15.8756(5) Å, b = 13.3707(4) Å, c = 13.3083(4) Å, β = 93.584(2)º, and V = 2819.40(15) Å for the Yb(III) polymer. The main findings in the structures of the new compounds are their isomorphism (due to the similarity between erbium and ytterbium ionic radii) and the coexistence in both of highly aqueous coordinated [Na(OH)(HO)] and [Ln(NO)] units. The luminescence measurements in the near infrared region after excitation at different wavelengths have confirmed the deleterious effect (quenching) of OH and HO groups on the emission (intensity and lifetime) of both erbium(III) and ytterbium(III) and the very weak optical absorption of lanthanides. Magnetic measurements show a paramagnetic behavior of the lanthanide centers. Graphical Abstract: Two new isostructural alkali-lanthanide coordination polymers, [Na(OH)(HO)Er(NO)] and [Na(OH)(HO)Yb(NO)], have been synthesized and characterized by X-ray diffraction. Their photoluminescent and magnetic properties are presented.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]