[Synthesis, characterization and fluorescent property of terbium binary and ternary complexes with p-aminohippuric acid].

A series of binary and ternary rare-earth compounds were synthesized by the reaction of terbium ion with p-aminohippuric (PAH, HL) acid and phenanthroline (phen) or 2,2'-bipyridine(2,2'-bpy) in the ethanol solution. The compositions of the complexes were deduced to be TbL3(1), TbL3.phen.H2O(2) and TbL3.bipy.H2O(3) by elemental analysis, TG-DTA, UV-Vis and IR, and the spectra and fluorescent properties of the complexes 1-3 were discussed. The oxygen atoms of the carboxylate group were coordinated with the rare-earth ion in bridging bidentate mode. The result shows that the higher the extent of the ligand coplanarity and conjugation, the better the fluorescent performance of the compound. The fluorescent intensity of the ternary complexes 2 and 3 are stronger than that of the binary complex 1.

Targeted self-assembly and quantum Monte Carlo magnetic study of an alternating nickel(II) 1D coordination polymer composed of highly preorganized binuclear tectons.

A pyrazolate-based binucleating ligand HL with pyridyl groups in the chelate arms has been used to synthesize the dinickel(II) complex [LNi2(N3)(MeOH)2](ClO4)2 (1) and the corresponding 1D polymeric [LNi2(mu-N3)2]n(NO3)n (2) depending on the amount of NaN3 added. X-Ray crystallography shows that structural parameters of the (LNi2(N3)) units are very similar in both compounds. This is ascribed to pi-pi stacking between the pyridyl rings that leads to rigidification of the framework and a fixed cis-orientation of the remaining coordination sites, which are filled by MeOH molecules in or by a mu1,3-bridging azide that connects the subunits in 2. Variable-temperature magnetic measurements reveal strong antiferromagnetic coupling with parameters g = 2.21 and J = -60.7 cm(-1) for compound 1. Magnetic data for the extended chain 2 have been analyzed by Quantum Monte Carlo (QMC) simulations to give g = 2.34, J1 = -55 cm(-1), and J2 = -12 cm(-1). The known J value for finally allows unambiguous assignment of J1 to the intrasubunit coupling within each bimetallic chain constituent. The alternation ratio gamma = J2/J1 signifies a singlet-dimer ground state of the new 1D polymer 2.

[Synthesis and spectral characterization of rare-earth-3-hydroxyl-2-naphthalinate-phenanthroline compounds].

The solid rare-earth (RE=Tb, Eu, Sm, Nd) compounds with 3-hydroxyl-2-naphthalinic acid (L) and phenanthroline (phen) were synthesized in ethanol solution in the present work. Their compositions were determined to be REL4 x phen2 x Na x H2O by the element analysis, infrared and ultraviolet absorption spectra, and DTA-TGA, respectively. The spectral properties of the compounds were studied tentatively, and the coordination mode of carboxyl group was deduced to be bridged style to chelate the rare-earth and sodium ions to form an infinite chain structural complex. The sodium and rare-earth ions are six-coordinated and eight-coordinated geometry respectively.

[Synthesis and spectral characterization of rare-earth-ortho-amino phenylbenzoate-2,2'-bipyridine complexes].

The solid rare-earth complexes were synthesized using rare-earth ions (RE=Tb, Nd, Sm, La) reacting with ortho-amino phenylbenzoic acid (L) and 2,2'-bipyridine (bipy). Their compositions were confirmed and the spectral properties were characterized by element analysis, infrared and ultraviolet absorption spectra, and DTA-TGA. The fluorescent properties of complexes TbL3 and TbL3 x bipy x 3H2O were also measured and discussed. The result shows that the fluorescence intensity of TbL3 x bipy 3H2O is stronger than that of TbL3.

[Synthesis, characterization and fluorescent property of ternary complexes of rare-earth, cinnamic acid and 2,2'-bipyridine].

The ternary rare-earth complexes were synthesized using cinnamic acid (L), 2,2'-bipyridine (bipy) and rare-earth (RE= Tb, Eu, Gd, Nd) in ethanol solution. Their compositions were confirmed to be REL3 x bipy by the element analysis, infrared and ultraviolet absorption spectra, and DTA-TGA, respectively. The spectral properties of complexes and the fluorescent property of EuL3 x bipy were discussed. The fluorescence intensity of EuL3 is 4.5 times stronger than that of EuL3 x bipy x H2O.

[Synthesis and fluorescence property of complexes of rare-earth with p-nitrophenylacetic acid].

The binary solid complexes had been synthesized using rare-earth ion with p-nitrophenylacetic acid. The chemical formula of ReL3.H2O(Re = Eu, Sm, Tb) complexes was determined by elemental analysis, molar conductivity, and TG-DTA. The composition structure and properties of the binary complexes were tentatively investigated by the analysis of IR, UV, and fluorescence spectra. The IR showed the carboxylic ligand chelates to the center ion to form the complexes, and the complexes contain water molecule of hydration. The result above was also proved by comparison of UV of the ligand and complexes. Two bands of strong red fluorescence of ReL3.H2O may be contributed to the fluorescence spectra of 5D0-->7 F1 and 5D0-->7 F2 transition of Eu3+.