In one word,h ow would you describe your research? Spectacular!Did serendipity play apart in this work?Serendipity plays ac ontinuous role in our research, from the initial discovery of this novel class of extremely efficient anion incarcerating agents, which we termed nanojars, to the current results presented here.What was the biggest surprise (on the way to the results presented in this paper)?Given the structural complexity and novelty of nanojars, certainly nobody could have predicted the effect of ammonia on an anojar mixture. It was indeed ah uge surprise to find that one of the five homologous nanojars in the mixture is totally resistant to the action of NH 3 in solution, while the other four break down and rearrange into the NH 3 -resistant one.What was the biggest challenge( on the way to the results presented in this paper)?Although nanojars are readily synthesized, they always form as am ixture of nanojars of different sizes. Apart from crystallization that occasionally results in af ew small crystals, all common separation methods failed to provide larger samples of pure, individual nanojars. What aspects of this project do you find most exciting?This project involves ac omplex array of techniques, including covalent synthesis of new organic ligands, supramolecular/coordination self-assembly,X -ray crystallography,m ass spectrometry and nuclear magnetic resonance techniques, which all unveil unique, intriguing results about nanojars, and point to potential applications. The most exciting part of our research always is designing the next step, and awaiting for the results of the new experiments. Does the research open other avenues that you would like to investigate?One new avenue we are currently exploring is the selective extraction of anions from contaminated water,i ncluding highly toxic anions, such as arsenate, chromate and selenate, using nanojars.Invited for the cover of this issue is the team led by Gellert Mezeia tW estern Michigan University.T he image depicts "ammonia" selectively breakingd own nano jar mixtures into pure nanojar species, but one resists!R ead the full text of the arti-

In one word,h ow would you describe your research? Spectacular! Did serendipity play apart in this work? Serendipity plays ac ontinuous role in our research, from the initial discovery of this novel class of extremely efficient anion incarcerating agents, which we termed nanojars, to the current results presented here. What was the biggest surprise (on the way to the results presented in this paper)? Given the structural complexity and novelty of nanojars, certainly nobody could have predicted the effect of ammonia on an anojar mixture. It was indeed ah uge surprise to find that one of the five homologous nanojars in the mixture is totally resistant to the action of NH 3 in solution, while the other four break down and rearrange into the NH 3-resistant one. What was the biggest challenge(on the way to the results presented in this paper)? Although nanojars are readily synthesized, they always form as am ixture of nanojars of different sizes. Apart from crystallization that occasionally results in af ew small crystals, all common separation methods failed to provide larger samples of pure, individual nanojars. What aspects of this project do you find most exciting? This project involves ac omplex array of techniques, including co-valent synthesis of new organic ligands, supramolecular/coordina-tion self-assembly,X-ray crystallography,m ass spectrometry and nuclear magnetic resonance techniques, which all unveil unique, intriguing results about nanojars, and point to potential applications. The most exciting part of our research always is designing the next step, and awaiting for the results of the new experiments. Does the research open other avenues that you would like to investigate? One new avenue we are currently exploring is the selective extraction of anions from contaminated water,i ncluding highly toxic anions, such as arsenate, chromate and selenate, using nanojars. Invited for the cover of this issue is the team led by Gellert Mezeia tW estern Michigan University.T he image depicts "am-monia" selectively breakingd own nano jar mixtures into pure nanojar species, but one resists!R ead the full text of the arti

Five compounds based on the versatile pyrazole-4-sulfonate anion (4-SO 3 -pzH ¼ L À ) were synthesized by the reaction of ligand HL with ZnO, CdCO 3 , Ag 2 O, NaOH and NH 3 , respectively. Crystals of Zn(4-SO 3 -pzH) 2 (H 2 O) 2 , Cd(4-SO 3 -pzH) 2 (H 2 O) 2 , Ag(4-SO 3 -pzH), Na(4-SO 3 -pzH)(H 2 O) and NH 4 (4-SO 3 -pzH) were obtained from aqueous solutions upon evaporation, and were characterized by single-crystal X-ray diffraction, IR and NMR spectroscopy, thermogravimetric analysis and copper corrosion inhibition experiments. We found that the non-isomorphous, 3-dimensional inorganic-organic layered solid state structure of these compounds is determined by an intricate interplay between the size, charge and coordination preference of the cation, and an extended lattice of hydrogen bonds and aromatic interactions. Ligand L À incorporates a host of different binding capabilities (metal coordination through the pyrazole N-atom and/or the sulfonate O-atom, hydrogen-bonding both as donor and acceptor, p-p and C-H/p interactions). Thin films formed by these complexes on copper metal surfaces were studied by optical microscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy. ZnL 2 , CdL 2 , AgL and NH 4 L, in addition to the free ligand HL, were tested as corrosion inhibitors on copper metal surfaces at three different pH values (2, 3 and 4), and the corrosion rates were quantified. Significant corrosion protection was observed with all compounds at pH 4 and 3.

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A series of 11 compounds, including alkali (Li, Na, K, Rb, Cs) and alkaline-earth (Mg, Ca, Sr, Ba) coordination polymers, transition-metal (Cu, Cd) complexes, and the ammonium salt of 3,5-dimethylpyrazole-4-sulfonic acid (HL), were synthesized. Single crystals of HL, and CdL 2 (H 2 O) 3 •2H 2 O were obtained from aqueous solutions either by evaporation or acetone vapor diffusion. Characterization by single-crystal X-ray diffraction reveals that the coordination compounds of L − (except Cu) possess alternating inorganic−organic layered structures, in which L − engages in extensive charge-assisted networks of H-bonding and aromatic interactions as well as metal coordination through the pyrazole N atom and/or the sulfonate O atom. A topological analysis and classification of underlying metal−organic or hydrogen-bonded networks uncover a number of distinct topological nets (3,5L2, hcb, 6,6L1, 3,5C1, 3,8L28, hex, and pcu). A thermogravimetric analysis shows that HL and NH 4 L are stable up to 285 and 90 °C, respectively, whereas the anhydrous metal compounds decompose above 200−230 °C. The pK a values of 3,5-dimethylpyrazole-4-sulfonic acid (HL) and pyrazole-4-sulfonic acid were determined by 1 H NMR titrations with H 2 SO 4 . Copper corrosion experiments indicate that 3,5-dimethylpyrazole-4sulfonic acid (HL) is a better anticorrosion agent than the parent pyrazole-4-sulfonic acid at pH 4, whereas the coordination polymers of L − offer weaker corrosion protection in comparison to the corresponding pyrazole-4-sulfonate complexes. The latter result is corroborated by the less compact and less robust thin films formed by metal−L compounds, as indicated by scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) measurements, and the weaker acidity of HL, which allows for easier protonation of the conjugate base L − in metal−L compounds.