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This week The Alchemist looks at extraterrestrial cyanide, chemistry at speed with nanoalloys, the real reason batteries fail, the ionization of lawrencium and gold nanoparticles. Finally, an oily award.




An international collaboration has measured the first ionization energy of the heaviest actinide lawrencium - the synthetic radioactive element 103. Led by researchers from the Japan Atomic Energy Agency (JAEA) in Tokai, the team obtained a value of 4.96 electronvolts. "We found that the energy required to remove the outermost electron in lawrencium was the lowest among all the actinides," explains team member Christoph Düllmann of Johannes Gutenberg University Mainz (JGU), Germany. The measurement confirms the position of lawrencium as the last actinide and also vindicates the structure of the periodic table of elements.





Rongchao Jin of Carnegie Mellon University in Pittsburgh, Pennsylvania, USA, and colleagues have obtained an X-ray structure of the gold nanoparticle, Au133, which comprises 133 gold atoms and 52 surface-protecting molecules. It is the biggest nanoparticle structure resolved with X-ray crystallography. "With X-ray crystallography, we were able to see very beautiful patterns, which was a very exciting discovery. These patterns only show up when the nanoparticle size becomes big enough," Jin explains. The experiments revealed that during formation the nanoparticles self-assemble into three layers within each particle: the gold core, the surface molecules that protect it and the interface between the two. The X-ray data reveal the core to be icosahedral and the interface between the core and the surface-protecting molecules to be composed of a layer of sulfur atoms bonded to the gold atoms stacked into helical ladder-like structures. The outer layer of molecules have carbon tails that self-assemble into fourfold swirls.





Yeonhwa Park of University of Massachusetts Amherst is this year's winner of the Timothy L. Mounts Award for her "significant and important contributions in the area of bioactive lipids and their impact on health conditions such as obesity, osteoporosis, arthritis and cardiovascular disease." The award given by the American Oil Chemists' Society comes with a plaque, a $750 honorarium and the opportunity to deliver the lecture "Conjugated Linoleic Acid: 30-year Research," at the AOCS annual meeting in Orlando in May.





Data from the Atacama Large Millimeter/submillimeter Array (ALMA) has allowed astronomers to detect complex organic molecules - including methyl cyanide - in a protoplanetary disc surrounding a distant, young star MWC 480. The compound and its simpler cousin hydrogen cyanide were observed in the cold outer reaches of the star's newly formed disc, a region equivalent to our Solar System's Kuiper Belt where icy planetesimals and comets reside. "We now have even better evidence that this same chemistry exists elsewhere in the Universe, in regions that could form solar systems not unlike our own." This is particularly intriguing, lead author Karin Öberg says, as the molecules found in MWC 480 are also found in similar concentrations in Solar comets.





Palladium-nickel nanoalloy catalysts have tunable parameters, such as particle size and atomic composition, that affect critical atomic-scale structural features and specifically the rate at which they can catalyze the oxidation of carbon monoxide to carbon dioxide, according to researchers in China and the USA. "Key to understanding the structural-catalytic synergy is the use of high-energy synchrotron X-ray diffraction coupled to atomic pair distribution function (HE-XRD/PDF) analysis to probe the atomic structure of PdNi nanoalloys under controlled thermochemical treatments and CO reaction conditions," the team reports in the Journal of the American Chemical Society, JACS. Moreover, the new insights the team gained into the structural synergy of nanoalloy catalysts and how activity might be controlled through phase state, composition and atomic structure, complements density functional theory (DFT) studies, they add.





Rechargeable lithium ion are ubiquitous in modern mobile electronic gadgets but despite claims that they do not suffer from the debilitating "memory effects" of their nickel-cadmium predecessors, they do wear out with repeated charge cycles. Now, researchers at Pacific Northwest National Laboratory (PNNL) in Richland, Washington, USA, have demonstrated using powerful microscopy techniques that eruptions of lithium at the tip of a battery's electrode, cracks in the electrode's body, and a coat forming on the electrode's surface reveal how recharging a battery many times ultimately leads to its demise and an inability to recharge it again. "This work is the first visual evidence of what leads to the formation of lithium dendrites, nanoparticles and fibers commonly found in rechargeable lithium batteries that build up over time and lead to battery failure," explains lead scientist Nigel Browning. "Once you can image this," he says, "why cycle a battery for days and days and days when you know how quickly the battery decays? Now we can cut down on cycling and move on to testing individual characteristics of new battery chemistries."