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Novel mononuclear lanthanide thiocyanates with 2,2′;6′,2″-terpyridine (terpy), namely isomorphic complexes [Ln(terpy)2(NCS)3] (Ln = Y, Eu, Tb and Dy) were prepared and studied. The effective luminescence sensitization of the Eu, Tb and Dy ions owing to the terpy ligands was observed and corresponding values of the absolute quantum yields were determined. The influence of structural features of the complexes studied on their luminescent properties was analyzed. Slow magnetic relaxation indicating SMM behavior was found for Dy complex.

Heterometallic {Zn-Ln}-complexes [Zn2Ln(OH)(Piv)4(NO3)2(pyzphen)2], where Ln is Eu (1), Gd (2) or Tb (3), Piv- is an anion of pivalic acid and pyzphen is pyrazino[2,3-f][1,10]phenanthroline, were synthesized. Crystallographic cell parameters and XRPD study show the compounds to be isostructural. The crystal structure of 3 was determined by single crystal X-ray analysis. The complexes contained two pyzphen ligands coordinated by Zn ions. Inter- and intra-molecular interactions between aromatic fragments of pyzphen resulted in the formation of a stack structure. The triplet state energy of pyzphen in complex 2 is 22200 cm−1. Analysis of the luminescence of 1 and 3 showed a low efficiency of ligand-to-metal energy transfer.

A series of complexes [(4,4′-diMe-2,2′-bpy)2Zn2Eu2(NO3)4(naphac)6] (1), [(4,4′-dtb-2,2′-bpy)2Zn2Ln2(NO3)2(naphac)8] Ln = Eu (2), Tb (3), [(Py)2Zn2Ln2(naphac)10] Ln = Eu (4), Nd (5), Gd (6), Tb (7), Dy (8), [(Py)2Zn2Tm2(NO3)2(naphac)8] (9) (where naphac is the anion of 1-naphthylacetic acid, 4,4′-diMe-2,2′-bpy = 4,4′-dimethyl-2,2′-bipyridine, 4,4′-dtb-2,2′-bpy = 4,4′-di-tert-butyl-2,2′-bipyridine, Py = pyridine) were synthesized and structurally characterized. Capabilities of several synthetic routes for obtaining the title compounds were evaluated. Molecular and crystal structures as well as luminescence properties of obtained heterometallic complexes are reported and discussed in detail.

Heterometallic complex [Cd2Eu(bzo)6(NO3)(MeCN)2(THF)2].2EtOH was synthesized by the reaction of Cd(NO3)2·4H2O and Eu(NO3)3·6H2O with potassium 3,5-di-tert-butylbenzoate (Hbzo). N-Donors (L) could replace solvents in the Cd coordination environment without modifying the stable metal core {Cd2Eu(bzo)6(X)} (X = NO3 or bzo). The presence of pyrazine (pz) in the reaction mixture could result in the formation of either molecular [Cd2Eu(bzo)6(NO3)(pz)2(EtOH)2] or 1D-polymeric [Cd2Eu(bzo)6(NO3)(pz)(H2O)2]n complex, depending on the Cd : L molar ratio (1 : 15 and 1 : 8, respectively). Addition of bridging N-donors 4,4′-bipyridine (4,4′-bipy) and 1,2-bis(2-pyridyl)ethylene (bpe) (Cd : L = 1 : 2) gave the [Cd2Eu(bzo)7(4,4′-bipy)(H2O)2]n and [Cd2Eu(bzo)7(bpe)(H2O)2]n polymers, respectively. 4-Methyl-2-aminopyridine (ampy) gave only molecular compound [Cd2Eu(bzo)7(ampy)2(EtOH)(H2O)] (Cd : L = 1 : 3). The structures of all the resulting compounds were studied by single crystal X-ray diffraction analysis. Photoluminescent properties were studied for solid samples of the synthesized compounds. The effect of the N-donor ligand geometry and the Eu…Eu distance on the lifetime of the Eu3+ atom’s 5D0 excited state is discussed.