Guest molecular guided syntheses of 2-dimensional uranyl complexes with rigid benzenedicarboxylate ligands

• Published in: Journal of coordination chemistry Vol. 76; no. 2; pp. 292 - 306
• Main Authors: Wu, Hong-Yan, Luo, Ju-Xiang, Li, Hao-Hong, Zhang, Jian-Han
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 17.01.2023; Taylor & Francis Ltd
• Subjects: Crystal structure; Crystallization; Heterometallic; Ligands; Light emission; luminescence; Single crystals; Thermal stability; Uranium dioxide; uranyl complexes
• ISSN: 0095-8972; 1029-0389
• DOI: 10.1080/00958972.2023.2170230

Two new heterometallic uranyl-organic frameworks (UOFs), [Cd(phen) 2 (H 2 O) 2 ][(UO 2 ) 2 (BDC) 3 ]·2H 2 O (1) and [Ni(phen) 3 ][(UO 2 ) 2 (BDC) 3 ]·2H 2 O (2), were obtained under hydrothermal conditions. Both crystal structures were characterized by single-crystal X-ray diffraction analyses and the results indicate that both complexes feature a similar 2D honeycomb framework that is connected by rigid benzenedicarboxylate (BDC) ligands and uranyl units. BDC works as a linker to bridge neighboring UO 2 2+ units, where UO 2 2+ is tris-chelated. Different guest molecules guided the stacking of 2D layers and lead into their 3D supramolecular crystal structures with different space groups. As a result, 1 crystallized in a polar space group Cc, whereas 2 belongs to a chiral space group P6 1 22. Thermogravimetric measurements were performed to study their thermal stability. UV-visible diffuse reflectance spectroscopy measurements indicate an experimental optical bandgap of 3.87 eV and 3.63 eV, respectively, for 1 and 2. Luminescent studies of both samples show strong green light emissions.