物理化学学报 >> 2023, Vol. 39 >> Issue (1): 2206035.doi: 10.3866/PKU.WHXB202206035

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卤代芳香族羧酸与含氮配体合成镧系配合物的结构、热化学和荧光性质

王晨璐1, 宿素玲2, 任宁3,*(), 张建军1,*()   

  1. 1 河北师范大学分析测试中心, 化学与材料科学学院, 石家庄 050024
    2 河北省特种设备监督检验研究院, 石家庄 050000
    3 邯郸学院, 化学化工与材料学院, 河北省杂环化合物重点实验室, 河北 邯郸 056005
  • 收稿日期:2022-06-24 录用日期:2022-07-12 发布日期:2022-07-20
  • 通讯作者: 任宁,张建军 E-mail:ningren9@163.com;jjzhang6@126.com
  • 基金资助:
    国家自然科学基金(22273015);国家自然科学基金(21803016)

Construction, Thermochemistry, and Fluorescence Properties of Novel Lanthanide Complexes Synthesized from Halogenated Aromatic Carboxylic Acids and Nitrogen-Containing Ligands

Chenlu Wang1, Suling Xu2, Ning Ren3,*(), Jianjun Zhang1,*()   

  1. 1 Testing and Analysis Center, College of Chemistry & Material Science, Hebei Normal University, Shijiazhuang 050024, China
    2 Hebei Special Equipment Supervision and Inspection Institute, Shijiazhuang 050000, China
    3 College of Chemical Engineering & Material, Hebei Key Laboratory of Heterocyclic Compounds, Handan University, Handan 056005, Hebei Province, China
  • Received:2022-06-24 Accepted:2022-07-12 Published:2022-07-20
  • Contact: Ning Ren,Jianjun Zhang E-mail:ningren9@163.com;jjzhang6@126.com
  • About author:Email: ningren9@163.com; +86-310-6260302 (R.N.)
    Email: jjzhang6@126.com; Tel.: +86-311-80786457 (Z.J.)
  • Supported by:
    the National Natural Science Foundation of China(22273015);the National Natural Science Foundation of China(21803016)

摘要:

采用室温溶液挥发法合成了五种结构新颖的镧系配合物,其结构通式为[Ln(2, 4-DFBA)3(phen)]2 (Ln = Sm 1, Eu 2, Er 3, 2, 4-DFBA为2, 4二氟苯甲酸的简写,phen为1, 10-菲啰啉的简写), [Ln(2-Cl-6-FBA)2(terpy)(NO3)(H2O)]2 (Ln = Tb 4, Dy 5, 2-Cl-6-FBA为2-氯-6-氟苯甲酸的简写, terpy为2, 2’: 6’2’’-三联吡啶的简写)。五个配合物可以分为两个系列,使用不同的镧系离子作为中心离子。通过X射线单晶分析,5种配合物均属于单斜晶系,空间群为P21/n。配合物12和配合物3虽然具有相同的分子通式,但配位方式明显不同,形成了前者为9配位的松饼型,后者是8配位的双帽三棱柱几何构型。二维面状超分子结构的形成方式也明显不同,区别在于配合物12通过微弱的π-π堆积作用形成。配合物45是同构的,结构中引入了硝酸根离子较为有趣,通过C―H∙∙∙F氢键和π-π堆积作用形成二维面状超分子结构。在299.25–1073.15 K温度下对配合物1–5通过热重-微分热重-差示扫描量热/红外光谱(TG-DTG-DSC/FTIR)联用技术进行热分解机理的研究。测定了配合物1, 2, 4, 5的固体荧光,特征过渡峰位于4G5/26H5/2, 4G5/26H7/2, 4G5/26H9/2 (1), 5D07F0, 5D07F1, 5D07F2, 5D07F3, 5D07F4 (2), 5D47F6, 5D47F5, 5D47F4, 5D47F3 (4), 和4F9/26H15/2, 4F9/26H13/2 (5),均表现出镧系离子的特征过渡峰。此外,还对配合物24进行了荧光寿命的研究,其荧光衰减时间分别为1.288和0.648 ms。

关键词: 镧系配合物, 超分子结构, 热化学, 三维红外, 荧光性质

Abstract:

In this study, new lanthanide complexes were synthesized via the volatilization method in solution at room temperature. The general molecular formulas for the lanthanide complexes are as follows: [Ln(2, 4-DFBA)3(phen)]2 (Ln = Sm 1, Eu 2, and Er 3; 2, 4-DFBA = 2, 4-difluorobenzoate; and phen = 1, 10-phenanthroline), as well as [Ln(2-Cl-6-FBA)2(terpy)(NO3)(H2O)]2 (Ln = Tb 4 and Dy 5; 2-Cl-6-FBA = 2-chloro-6-fluorobenzoate; and terpy = 2, 2': 6'2''-tripyridine). Based on single-crystal X-ray analysis, the five complexes exhibited a monoclinic crystal structure belonging to the space group P21/n. Even though complexes 1, 2 (I), and 3 (II) share a general molecular formula, their coordination modes were different. For example, complexes 1 and 2 formed a muffin-like structure with nine coordinated atoms, while complex 3 formed a double hat triangular geometry with eight coordinated atoms. The two-dimensional (2D) polyhedral structures of complexes 1 and 2 were formed via weak π-π stacking interactions, whereas complex 3 exhibited a 2D faceted supramolecular structure through C―H∙∙∙F hydrogen bonds. Complexes 4 and 5 were isostructural, with the presence of nitrate ions in their structure. This occurred through the C―H∙∙∙F hydrogen bonds and π-π stacking of the molecules to form a faceted supramolecular crystal structure. A series of characterizations, such as elemental analysis, infrared and Raman spectroscopy, as well as powder X-ray diffraction, were performed on the five complexes. Thermogravimetry-derivative thermogravimetry-differential scanning calorimetry were performed between 299.25 and 1073.15 K to investigate the mechanism for the thermal decomposition of complexes 15. The analysis of the escaping gas stacking maps of the five complexes using thermogravimetric and 3D infrared coupling techniques further confirmed the correctness of the thermal decomposition mechanism of each complex. The results obtained revealed that similar structured complexes follow a similar thermal decomposition mechanism, and the end solid products for all complexes were their corresponding metal oxides. During the irradiation of the Xe lamp, the solid fluorescence of complexes 1, 2, 4, and 5 were measured. The characteristic transition peaks were located at 4G5/26H5/2, 4G5/26H7/2, and 4G5/26H9/2 (1); 5D07F0, 5D07F1, 5D07F2, 5D07F3, and 5D07F4 (2); 5D47F6, 5D47F5, 5D47F4, and 5D47F3 (4); and 4F9/26H15/2, 4F9/26H13/2 (5). The peaks observed indicated the characteristic transitions of Ln(III). The lanthanide complexes exhibited characteristic fluorescence due to this fact, which also explained their characteristic color. Furthermore, the fluorescence lifetimes of complexes 2 and 4 were measured, and their fluorescence decay curves indicated fluorescence lifetimes of 1.288 and 0.648 ms, respectively.

Key words: Lanthanide complexes, Supramolecular structure, Thermochemistry, Three-dimensional infrared, Fluorescent properties

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