The effect of the second coordination sphere on the magnetism of [Ln(NO3)3(H2O)3]·(18-crown-6) (Ln = Dy and Er)
| Autor: | Ivan Nemec, Radovan Herchel, Pavel Zoufalý |
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| Rok vydání: | 2019 |
| Předmět: |
Materials science
Coordination sphere Condensed matter physics Magnetism General Chemical Engineering Magnetization reversal 18-Crown-6 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Metal chemistry.chemical_compound Magnetic anisotropy chemistry Magnet visual_art visual_art.visual_art_medium Molecule 0210 nano-technology |
| Zdroj: | RSC Advances. 9:569-575 |
| ISSN: | 2046-2069 |
| DOI: | 10.1039/c8ra09648a |
| Popis: | The objective of this work was the exploration of the effect of the second coordination sphere on the magnetic properties of [Ln(NO3)3(H2O)3]·(18C6) (Ln = Dy (1) and Er (2)) compounds comprising co-crystallized 18-crown-6 ethers. Both compounds were identified as field-induced single molecule magnets (SMMs) with estimated magnetization reversal barriers Ueff = 66–71 K for 1 and Ueff = 21–24 K for 2. Theoretical calculations with the B3LYP functional revealed substantial change and redistribution of the electrostatic potential upon accounting for the second coordination sphere represented by two 18C6 molecules, which resulted in the change of the crystal-field around metal atoms. As a result, the multireference CASSCF calculations exposed significant impact of the second coordination sphere on the energy splitting of the respective 6H15/2 (DyIII) and 4I15/2 (ErIII) ground states, the magnetization reversal barrier and the magnetic anisotropy parameters. Moreover, the calculated magnetization reversal barriers, Ucalc. = 57 K for 1 and Ucalc. = 16 K for 2, are in good agreement with the experimental values accentuating the importance of the second coordination sphere on the magnetic properties of SMMs. |
| Databáze: | OpenAIRE |
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