The syntheses, structure and magnetic properties are reported for five novel 1D polymeric azido-bridged lanthanide complexes with the general formula {[Ln-(DAPMBH)(N 3 )C 2 H 5 OH]C 2 H 5 OH} n where H 2 DAPMBH = 2,6-diacetylpyridine bis(4-methoxybenzoylhydrazone)a new pentadentate pyridine-base [N 3 O 2 ] ligand and Ln = Dy (1), Y 0.930 Dy 0.070 (2), Er (3), Y 0.923 Er 0.077 (4), and Gd (5). Xray diffraction analysis of 1−5 show that the central lanthanide atoms are eight-coordinated with the N 5 O 3 donor set originating from the ligand DAPMBH, one coordinated ethanol molecule and two end-to-end type N 3 − bridges connecting the metal centers into infinite chain. The [LnN 5 O 3 ] coordination polyhedron can be regarded as a distorted dodecahedron (D 2d). AC magnetic measurements revealed that compounds 1−4 show field-induced single-molecule magnet behavior, with estimated energy barriers U eff ≈ 47−17 K. The experimental study of magnetic properties was complemented by theoretical analysis based on crystal-field calculations. Direct current magnetic susceptibility studies revealed marginally weak intrachain exchange interaction between Ln 3+ ions mediated by the end-to-end azide bridging groups (J ≈ −0.015 cm −1 for 5). Comparative analysis of static and dynamic magnetic properties of magnetically concentrated (1, 3) and diluted (2, 4) Dy and Er compounds showed that, despite fascinating 1D azido-bridged chain structure, compounds 1 and 3 are not single-chain magnets; their magnetic behavior is largely due to single-ion magnetic anisotropy of individual Ln 3+ ions.

A series of new Eu-doped layered yttrium hydroxides intercalated with various organic dianions having similar molecular structure (dicarboxylates and sulphobenzoates) were synthesized.

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