Bismuth Coordination Polymers with 2,4,6‐Pyridine Tricarboxylic Acid: High‐Throughput Investigations, Crystal Structures and Luminescence Properties

• Published in: European journal of inorganic chemistry Vol. 2018; no. 27; pp. 3232 - 3240
• Main Authors: Rhauderwiek, Timo, dos Santos Cunha, César, Terraschke, Huayna, Stock, Norbert
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 23-07-2018
• Subjects: 2,4,6‐Pyridinetricarboxylic acid; Bismuth; Coordination polymers; Crystal structure; High‐throughput methods; Hydrothermal reactions; Inorganic chemistry; Luminescence; Optical properties; Organic chemistry; Polymers; Reproducibility; Sodium hydroxide; Ultraviolet radiation; X-ray diffraction
• DOI: 10.1002/ejic.201800154
• EISSN: 1099-0682
• ISSN: 1434-1948

Four new coordination polymers (CPs) were obtained under hydrothermal reaction conditions using 2,4,6‐pyridinetricarboxylic acid (H3PTC) and Bi(NO3)3·5H2O. The systematic high‐throughput investigation of the system Bi3+/H3PTC/NaOH/HNO3/H2O led to the compounds [Bi(PTC)(H2O)2] (1), (H3O)[Bi2(PTC)(HPTC)2(H2O)2] (2), α‐[Bi(PTC)] (3) and β‐[Bi(PTC)] (4), which were structurally characterised by single‐crystal X‐ray diffraction. Compounds 1 and 2 crystallise in 2D layered structures, whereas 3 and 4 form 3D coordination networks. Employing the nomenclature proposed by Cheetham et al. 1 and 2 are classified as I1O1 (mixed inorganic–organic layers), 3 as I0O3 (3D coordination polymers) and 4 as I1O2 (mixed inorganic–organic 3D framework). In all cases the nitrogen atom of the linker is coordinated to the Bi3+ ion, which therefore acts as a tridentate pincer‐type ligand. All title compounds were obtained as phase‐pure products employing conventional or microwave‐assisted heating, but the reproducibility of the synthesis depends on reactor size and material. In addition, the luminescence properties of 1 and 2 were studied resulting in a yellow and blue–green luminescence under UV light with emission maxima at 570 nm (λex = 343 nm) and 483 nm (λex = 347 nm) for 1 and 2, respectively. The differences in the spectroscopic properties could be assigned to the distinct coordination and chemical environments of the Bi3+ ions within these compounds.
The systematic high‐throughput investigation of the system Bi3+/pyridine tricarboxylic acid (H3PTC)/NaOH/HNO3 in H2O under solvothermal reaction conditions resulted in the discovery of four new Bi carboxylates exhibiting various coordination modes, inorganic building units and luminescence properties.