We have designed and synthesized an isoreticular series of luminescent metal-organic frameworks (LMOFs) by incorporating a strongly emissive molecular fluorophore and functionally diverse colinkers into Zn-based structures. The three-dimensional porous networks of LMOF-261, -262, and -263 represent a unique/new type of nets, classified as a 2-nodal, (4,4)-c net (mot-e type) with 4-fold, class IIIa interpenetration. All compounds crystallize in a body-centered tetragonal crystal system (space group I4/a). A systematic study has been implemented to analyze their interactions with heavy metals. LMOF-263 exhibits impressive water stability, high porosity, and strong luminescence, making it an excellent candidate as a fluorescent chemical sensor and adsorbent for aqueous contaminants. It is extremely responsive to toxic heavy metals at a parts per billion level (3.3 ppb Hg, 19.7 ppb Pb) and demonstrates high selectivity for heavy metals over light metals, with detection ratios of 167.4 and 209.5 for Hg/Ca and Hg/Mg, respectively. Mixed-metal adsorption experiments also show that LMOF-263 selectively adsorbs Hg over other heavy metal ions in addition to light metals. The Pb K value for LMOF-263 (55,017 M) is the highest among LMOFs reported to date, and the Hg K value is the second highest (459,446 M). LMOF-263 exhibits a maximum adsorption capacity of 380 mg Hg/g. The Hg adsorption process follows pseudo-second-order kinetics, removing 99.1% of the metal within 30 min. An in situ XPS study provides insight to help understand the interaction mechanism between Hg and LMOF-263. No other MOFs have demonstrated such a high performance in both the detection and the capture of Hg from aqueous solution.

The feasibility of the determination of sub ppm to percentage levels of halogen elements (fluorine, chlorine, bromine, and iodine) in solid organic compounds and drug substances by double focusing sector field highresolution inductively coupled plasma mass spectrometry (HR-ICP-MS) was investigated. Samples were dissolved in appropriate solvents and then diluted in either deionized water or 5% (v/v) ammonium hydroxide. By applying medium or high resolution, the background counts can be lowered by up to five orders of magnitude compared to conventional quadrupole ICP-MS systems. The signal sensitivities and memory effects of all four elements in different solvents were compared and assessed. The methods were applied to the determination of sub ppm to percentage levels of F, Cl, Br and I in a series of organic compounds and Merck drug substances. The results were found to be in excellent-to-reasonable agreement with the known or theoretical values of these compounds or drug substances. The limit of detection in solution for F was estimated to be 5 mg ml 21 (medium resolution), and for Cl, Br and I was 3 (high resolution), 0.08 (high resolution) and 0.03 (high resolution) ng ml 21 , respectively.

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Ir haVe been preViously reported to react with dinitrogen to giVe the bridging dinuclear complex [(PCP)Ir] 2 (N 2 ) (2), which was crystallographically characterized. We report that under N 2 atmosphere the only obserVable nitrogen complex in solution is actually the terminal dinitrogen complex (PCP)Ir(N 2 ). The mono-and dinuclear species are in equilibrium; the dinuclear complex more readily crystallizes from solution.