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Four new complexes [Ln(pfaa)3(H2O)2] n (Ln = Eu (1), Tb (2)) and [Ln2Cd2(pfaa)10 (phen)2(EtOH)2]·2MeCN (Ln = Eu (3), Tb (4), phen = 1,10-phenanthroline) based on pentaphorphenylacetic acid (Hpfaa) have been prepared and completely investigated. The structures of compounds 1 and 3 were studied by single crystal X-ray diffraction analysis: the isostructural complexes 1 and 2 represent 1D coordination polymer, while the isostructural complexes 3 and 4 are molecular compounds. Complexes 1–4 show strong lanthanide-centred luminescence, since the introduction of phenanthroline leads to a significant increase in the observed lifetime (τ obs) and photoluminescent quantum yield. New complexes of Eu3+ and Tb3+ with pentafluorophenylacetic acid have been studied. During synthesis under hydrothermal conditions, polymer structures are formed, while the introduction of phenanthroline and Cd2+ makes it possible to obtain molecular complexes. A change in the structure leads to significant changes in the luminescent properties. [ABSTRACT FROM AUTHOR]

Methods for the synthesis were developed and new homo- and heterometallic cadmium ([Eu2Cd2(MeCN)4(C6F5COO)10] (I), [Tb2Cd2(MeCN)6(C6F5COO)10]·4MeCN (II)) and zinc ([Zn(H2O)(C6F5COO)2] (III), [Eu2Zn2(MeCN)4(C6F5COO)10] (IV)) complexes were characterized. These complexes can be used as precursors for the synthesis of compounds with N-donor ligands. Complexes I and II differ in the coordination of the MeCN molecule, which is coordinated in II by each Tb3+ ion. Also, additional coordination of MeCN induces a greater distortion of the {Tb2Cd2} metal core of II. The crystal packing in I–IV is stabilized by numerous intermolecular O...H, F...F, C–H...F, and C–H...O contacts. The new compounds were characterized by single crystal X-ray diffraction (CCDC no. 2076524 (I), 2082731 (II), 2082803 (III), 2076525 (IV)), IR spectroscopy, C,H,N elemental analysis, and powder X-ray diffraction. [ABSTRACT FROM AUTHOR]

Data on the synthesis and study of the crystal structure of [Li10(Piv)10(MeCN)2]n (I) and [Li6(Piv)6(MeCN)2]n (II) are presented. According to X-ray diffraction data (CIF files CCDC nos. 1957855 (I); 1955569 (II)), compounds I and II are 1D polymers composed of deca- and hexanuclear fragments, respectively, in which the lithium atoms are linked to one another by μ3- and μ4-bridging pivalate anions. [ABSTRACT FROM AUTHOR]

Conditions for chemical assembly of new heterometallic trinuclear pivalates [CdM(piv)L] (M = Mg, Ca, or Sr; piv is pivalate) were found. Reactions with the nonchelating ligand 2,4-lutidine (lut) gave the crystals of heterometallic complexes [CdM(piv)(lut)] (M = Mg ( 1), Ca ( 2), and Sr ( 3)). With the chelating ligand 1,10-phenanthroline (phen), only the homometallic dimer [Cd(piv)(phen)] ( 4) was obtained under these conditions. Yet heterometallic trinuclear complexes with 1,10-phenanthroline ([CdMg(piv)(HO)(phen)] ( 5), [CaCd(piv)(phen)] ( 6), and [CdSr(piv)(phen)]∙2MeCN ( 7)) were synthesized by reactions of phen with complexes 1- 3. For all the complexes obtained, the molecular and crystal structures as well as the details of their molecular architecture were determined. The thermal behavior of aqua complex 5 was studied by TG and DSC. The complex eliminated the water molecule between 130 and 180 °C with a high endothermic effect ( Q = 101 kJ mol) due to (1) intramolecular hydrogen bonds that stabilize its molecular architecture and (2) subsequent structural rearrangements. [ABSTRACT FROM AUTHOR]

Four new complexes [Ln(pfaa)3(H2O)2] n (Ln = Eu (1), Tb (2)) and [Ln2Cd2(pfaa)10 (phen)2(EtOH)2]·2MeCN (Ln = Eu (3), Tb (4), phen = 1,10-phenanthroline) based on pentaphorphenylacetic acid (Hpfaa) have been prepared and completely investigated. The structures of compounds 1 and 3 were studied by single crystal X-ray diffraction analysis: the isostructural complexes 1 and 2 represent 1D coordination polymer, while the isostructural complexes 3 and 4 are molecular compounds. Complexes 1–4 show strong lanthanide-centred luminescence, since the introduction of phenanthroline leads to a significant increase in the observed lifetime (τ obs) and photoluminescent quantum yield. New complexes of Eu3+ and Tb3+ with pentafluorophenylacetic acid have been studied. During synthesis under hydrothermal conditions, polymer structures are formed, while the introduction of phenanthroline and Cd2+ makes it possible to obtain molecular complexes. A change in the structure leads to significant changes in the luminescent properties. [ABSTRACT FROM AUTHOR]