Luminescent Dy^III single ion magnets with same N₆O₃ donor atoms but different donor atom arrangements, ‿span style='font-style: italic'>fac‿[Dy^III(HL^DL-ala)₃]·8H₂O and ‿sp

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• 作者：Daisuke Hamada^a ; Takeshi Fujinami^a ; Suguru Yamauchi^a ; Naohide Matsumoto^a ; ^{naohide@aster.sci.kumamoto-u.ac.jp" class="auth_mail" title="E-mail the corresponding author} ; Naotaka Mochida^b ; Takayuki Ishida^b ; Yukinari Sunatsuki^c ; Masanobu Tsuchimoto^d ; Cecilia Coletti^e ; Nazzareno Re^e
• 关键词：Dysprosium(III) ; Tridentate ligand ; Facial and meridional ; Luminescence ; Single ion magnet
• 刊名：Polyhedron
• 出版年：2016
• 出版时间：18 April 2016
• 年：2016
• 卷：109
• 期：Complete
• 页码：120-128
• 全文大小：2497 K

文摘

Two Dy^III complexes with same N₆O₃ donor atoms but different donor atom arrangements ‘fac’-[Dy^III(HL^DL-ala)₃]·8H₂O (class="boldFont">1) and ‘mer’-[Dy^III(HL^DL-phe)₃]·7H₂O (class="boldFont">2) were synthesized, where H₂L^DL-ala and H₂L^DL-phe are tridentate NNO ligands of N-[(imidazol-4-yl)methylidene]-class="smallcaps">dl-alanine and N-[(imidazol-4-yl)methylidene]-class="smallcaps">dl-phenylalanine, respectively. Each Dy^III ion is coordinated by three mono-deprotonated mono-negative NNO tridentate ligands to form a nona-coordination geometry of a tricapped trigonal prism (TTP). class="boldFont">1 consists of enantiomers ‘fac’-[Dy^III(HL^D-ala)₃] and ‘fac’-[Dy^III(HL^L-ala)₃], while class="boldFont">2 consists of ‘mer’-[Dy^III(HL^D-phe)₂(HL^L-phe)] and ‘mer’-[Dy^III(HL^D-phe)(HL^L-phe)₂]. The temperature dependence of the magnetic susceptibilities and field-dependence of the magnetization of two complexes showed the different magnetic profiles and the Stark splitting of the ground state ⁶H_15/2 due to the crystal field effect on Dy^III ion (4f⁹, J = 15/2, S = 5/2, L = 5, g_J = 4/3, ⁶H_15/2). Luminescence spectra were observed and the fine structures assigned to the ⁴F_9/2 → ⁶H_15/2 transitions are partially observed. class="boldFont">1 and class="boldFont">2 showed an out-of-phase signal with frequency-dependence in alternating current (ac) susceptibility under a dc bias field of 1000 Oe, indicative of field induced single ion magnet (SIM). The ac magnetic susceptibilities under 1000 Oe dc field of class="boldFont">2 showed the maximum peaks at the higher temperature than those of class="boldFont">1, indicating that the energy barrier of class="boldFont">2 is larger than that of class="boldFont">1.