Researchers at the Carnegie Institution of Washington (Washington DC, USA) have managed to make a remarkable alloy of hydrogen and oxygen from water! They used X-rays to dissociate water at high pressure to form a solid mixture, that is, an alloy, of molecular oxygen (O₂) and molecular hydrogen (H₂).

The researchers placed some water under an extremely high pressure, about 170,000 atmospheres (17 Gigapascals), using a diamond anvil and then beamed high-energy X-rays at the water. Nearly all the water molecules split and reformed as a solid alloy of O₂ and H₂. The X-rays are key to cleaving the O—H bonds in water. Without it, the water remains as a high-pressure form of ice known as ice VII. Ice VII is one of at least 15 kinds of ice that exist under various high pressure and variable temperature conditions.

Good to see that the complete works of Charles Darwin, one of the greatest scientists, are being published online by Cambridge University. Darwin Online features many newly transcribed or never-before-published manuscripts and is worth anyone's time to browse around for a while. The great English naturalist Charles Darwin (1809-1882) revolutionized our understanding of life on earth.

Everyone knows that elemental nitrogen exists in the atmosphere as dinitrogen, N₂. There is a triple bond between the two nitrogen atoms. This is true - but under certain conditions, a fascinating N-N single bonded phase has been characterized.

In 1985 it was predicted that at high pressure, nitrogen would transform to a solid with a single-bonded crystalline structure called polymeric nitrogen. Later, it was proposed that it whould have a cubic gauche (cg-N) structure. Experimental evidence was scant however until 2004 when a team of scientists from Germany and Russia managed to make the compound directly from molecular nitrogen at temperatures above 2000 K and pressures above 110 GPa using a laser-heated diamond cell. The material was characterized by X-ray and Raman scattering methods we have identified this as the polymeric nitrogen (cg-N).

The phase is a stiff with a bulk modulus ≥300 GPa. This is characteristic of strong covalent solids. The polymeric nitrogen is metastable. The structure of N is polymeric with each nitrogen bound to three other nitrogen atoms. At a pressure of 115 GPa, each N-N bond length is 1.346 ± 0.004 Å. The N-N-N angles are all about 108.8°, very close to the ideal tetrahedral angle of just over 109°.

It did not prove possible to recover the polymeric nitrogen by releasing the pressure - in other words the polymer reverts to normal dinitrogen. The authors speculate that this form of nitrogen is a new class of single-bonded nitrogen materials that may have unique energy capacity properties (more than five times that of the most powerful energetic materials).

References

1. "Single-Bonded Cubic Form Of Nitrogen", M.I. Eremets, A.G. Gavriliuk, I.A. Trojan, D.A. Dzivenko, and R. Boehler, Nature (Materials), 2004, 3, 558. [doi:10.1038/nmat1146]

Experiments conducted at the Flerov Laboratory of Nuclear Reactions (Joint Institute for Nuclear Research) at Dubna in Russia indicate that element 118 (ununoctium, Uuo) was produced. Not too much though, one atom in the spring of 2002 and two more in 2005.

The 2002 experiment involved firing a beam of ⁴⁸₂₀Ca at ²⁴⁹₉₈Cf. The experiment took 4 months and involved a beam of 2.5 x 10¹⁹ calcium ions to produce the single event believed to be the synthesis of ²⁹⁴₁₁₈Uuo.

²⁴⁹₉₈Cf + ⁴⁸₂₀Ca → ²⁹⁴₁₁₈Uuo + 3¹n

Arguments continue over science education in the UK.

Twenty First Century Science is a suite of new GCSE science courses for 14- to 16-year-olds and all schools in the UK can start the courses from September 2006. Schools can continue to offer separate Chemistry, Physics, and Biology courses.

Critics such as Sir Richard Sykes (rector of Imperial College London) is among many attack the new qualification. He warned a "dumbed down syllabus" may stop those who did not study chemistry, physics and biology individually from getting into good universities. Sir Richard Sykes stated on BBC News: "If you wish to have a dumbed-down syllabus for the general population that's fine. But for those who really want to go on and study a subject in depth, and particularly go to a good university like Imperial, then they'll never get there unless they study the individual subjects and take A-levels in these individual subjects." He wrote in a report from the Institute of Ideas think tank that: "A science curriculum based on encouraging pupils to debate science in the news is taking a back-to-front approach... Science should inform the news agenda, not the other way round."

Scientists at the Lawrence Berkeley National Laboratory in California, USA, have discovered that nanocrystals of germanium embedded in silica glass don't melt until the temperature rises almost 200 degrees Kelvin above the melting temperature of germanium in bulk. What's even more surprising, these melted nanocrystals have to be cooled more than 200 K below the bulk melting point before they resolidify. Such a large and nearly symmetrical "hysteresis" -- the divergence of melting and freezing temperatures above and below the bulk melting point -- has never before been observed for embedded nanoparticles.

Researchers from the Massachusetts General Hospital in Boston (USA) have announced that hydrogen sulfide (sulphide) gas, H₂S, can induce a state of suspended animation in mice while maintaining normal blood pressure. It is hoped that this result eventually will help in the treatment critically-ill patients. This result was presented at the American Physiological Society conference, "Comparative Physiology 2006: Integrating Diversity," in Virginia Beach, Virginai, USA, October 2006.

Hydrogen sulfide (sulphide) gas, sometimes called sewer gas, produces a noxious odour often described as a rotten egg smell. This highly toxic gas occurs naturally in swamps, some springs, and volcanoes.

The 2006 Ig Noble prize for chemistry has been announced and was awarded to Spanish researchers Antonio Mulet, José Javier Benedito and José Bon (University of Valencia), and Carmen Rosselló (University of Illes Balears), for their outstanding research: "Ultrasonic Velocity in Cheddar Cheese as Affected by Temperature." published in the Journal of Food Science, 1999, 66, 1038-41.

The Ig Noble prizes are administered by the publishers of the Annals of Improbable Research magazine. It's not always clear to me that the Chemistry Ig Noble prizes seem more related to other areas, and some non-chemistry prizes look as though the work was chemical, but never mind. For the record, here are a few of the more recent awards.

The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Chemistry for 2006 to Prof Roger D. Kornberg of Stanford University (Stanford, CA, USA) "for his studies of the molecular basis of eukaryotic transcription".

In order for our bodies to make use of the information stored in the genes, a copy must first be made and transferred to the outer parts of the cells. There it is used as an instruction for protein production – it is the proteins that in their turn actually construct the organism and its function. The copying process is called transcription. Roger Kornberg was the first to create an actual picture of how transcription works at a molecular level in the important group of organisms called eukaryotes (organisms whose cells have a well-defined nucleus). Mammals like ourselves are included in this group, as is ordinary yeast.

It's great to see a new book about the periodic table and this one is written by Eric Scerri, a world authority on the periodic table!

Dr. Eric Scerri is a leading philosopher of science specializing in the history and philosophy of the periodic table. He is also the founder and editor in chief of the international journal Foundations of Chemistry and is a full-time lecturer at UCLA where he regularly teaches classes of 350 chemistry students as well as classes in history and philosophy of science. You can buy this book from our WebElements Amazon Store or our WebElements Amazon UK Store.

The Periodic Table: Its Story and Its Significance

The periodic table is one of the most potent icons in science. It lies at the core of chemistry and embodies the most fundamental principles of the field. The one definitive text on the development of the periodic table by van Spronsen (1969), has been out of print for a considerable time. The present book provides a successor to van Spronsen, but goes further in giving an evaluation of the extent to which modern physics has, or has not, explained the periodic system. The book is written in a lively style to appeal to experts and interested lay-persons alike.

The Periodic Table begins with an overview of the importance of the periodic table and of the elements and it examines the manner in which the term 'element' has been interpreted by chemists and philosophers. The book then turns to a systematic account of the early developments that led to the classification of the elements including the work of Lavoisier, Boyle and Dalton and Cannizzaro. The precursors to the periodic system, like Döbereiner and Gmelin, are discussed. In
chapter 3 the discovery of the periodic system by six independent scientists is examined in detail.

Two chapters are devoted to the discoveries of Mendeleev, the leading discoverer, including his predictions of new elements and his accommodation of already existing elements. Chapters 6 and 7 consider the impact of physics including the discoveries of radioactivity and isotopy and successive theories of the electron including Bohr's quantum theoretical approach. Chapter 8 discusses the response to the new physical theories by chemists such as Lewis and Bury who were able to draw on detailed chemical knowledge to correct some of the early electronic configurations published by Bohr and others.

Chapter 9 provides a critical analysis of the extent to which modern quantum mechanics is, or is not, able to explain the periodic system from first principles. Finally, chapter 10 considers the way that the elements evolved following the Big Bang and in the interior of stars. The book closes with an examination of further chemical aspects including lesser known trends within the periodic system such as the knight's move relationship and secondary periodicity, as well at attempts to explain such trends.