Syntheses, crystal structures and magnetic properties of sandglass DyIII9 and irregular tetrahedron DyIII4 complexes
| Autor: | Cheng-Ling Yin, Qiao-Qiao Long, Zi-Wei Xu, Zhi-Quan Pan, Hui-Sheng Wang |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
chemistry.chemical_classification
Ketone 010405 organic chemistry Stereochemistry Chemistry chemistry.chemical_element Crystal structure 010402 general chemistry 01 natural sciences 0104 chemical sciences Square antiprism Ion Inorganic Chemistry Magnetic anisotropy Crystallography chemistry.chemical_compound Materials Chemistry Tetrahedron Dysprosium Hemiacetal Physical and Theoretical Chemistry |
| Zdroj: | Polyhedron. 141:69-76 |
| ISSN: | 0277-5387 |
| DOI: | 10.1016/j.poly.2017.11.025 |
| Popis: | The synthesis, crystal structures, and magnetic properties of a nonanuclear dysprosium complex [Dy9(μ3-OH)8(μ4-OH)2(N3)8{(py)2C(OCH3)O}8](OH)·4H2O (1, (py)2C(OCH3)OH = the hemiacetal form of di-2-pyridyl ketone) and a tetranuclear dysprosium complex [Dy4(μ4-O)(μ-N3)2(μ-OCH3)2(L)4](OH)2·3.5CH3OH (2, HL = 2-(benzothiazol-2-yl-hydrazonomethyl)-6-methoxyphenol) have been prepared and structural characterization. Nine DyIII ions in 1 form a sandglass with the eight DyIII atoms at the apexes and one DyIII ion located at the center of a square antiprism formed by eight DyIII ions, while four DyIII ions in 2 form an irregular tetrahedron. Complexes 1 and 2 have been investigated by direct current (dc) and alternating current (ac) susceptibility measurements. The ac susceptibility studies revealed that complexes 1 and 2 exhibit slow magnetic relaxation. Moreover, complex 2 shows two-step thermal magnetic relaxation with their energy barriers of about 15 K and 2.68 K, respectively. The orientations of the magnetic anisotropy of DyIII ions in 1 and 2 were also estimated by electrostatic calculations. |
| Databáze: | OpenAIRE |
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