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No. 71: Sep-Oct 1990

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Novel Forms Of Matter

Vanilla and chocolate niobium Clusters. What is the difference between "vanilla" and "chocolate" niobium? To begin with, these two forms of niobium are neither single atoms nor crystalline arrays of atoms. Both "flavors" of niobium consist of 19 niobium atoms (Nb19+ ), but the atoms are clustered differently, as illustrated. The different clusters react quite differently chemically. The "chocolate" niobium, on the right, is a capped icosahedron and reacts readily with hydrogen. The "vanilla" double pyramid (left) has flatter surfaces and does not readily combine with hydrogen.

Cluster research is embryonic, with new surprises popping up almost every day. Once a cluster size exceeds a few hundred atoms, its properties begin to resemble those of the bulk material. However, "cluster-assembled materials" have been made by attaching clusterto-cluster in a sort of patchwork quilt. Such materials have unique properties that are quite different from those of the normal crystalline and amorphous materials. (Pool, Robert; "Clusters: Strange Morsels of Matter," Science, 248:1186, 1990.)

Comment. One would expect that the effects of clustering would be important in biology, too. We obviously have a lot to learn about this new realm between single atoms/molecules and bulk materials.

Quasicrystals. Quasicrystals, once considered physically impossible, have been found easy to grow -- once one's mindset is corrected. At Bell Labs, for example, quasicrystals of an aluminum-cobaltcopper alloy reveal atoms packed together in pentagonal arrays -- the very geometry that crystallographers assured us could not exist. As one of the Bell researchers remarked, "Most of the ap plications are unimagined." This goes for the basic properties of quasicrystals, too. (Keller, John J.; "Bell Labs Confirms That New Form of Matter Exists," Wall Street Journal, February 8, 1990. Cr. J. Covey.)

Nitrogen molecules that shouldn't exist.

"Chemists in West Germany have discovered a compound of nitrogen which breaks one of the fundamental rules of chemistry. The molecule has five bonds and is 'an extremely stable species.' According to the text books, a nitrogen atom cannot form more than four bonds."

The unruly nitrogen atom lurks at the center of a tribonal bipyramid of 5 gold atoms. Should you ask to synthesize a few of these molecular anomalies, take some (phosphine-gold) ammonium tetrafluoroborate from your shelf and add (triphenylphosphine) gold tetrafluoroborate! (Emsley, John; "The Nitrogen Molecule that Shouldn't Exist," New Scientist, p. 30, May 26, 1990.)

From Science Frontiers #71, SEP-OCT 1990. 1990-2000 William R. Corliss

Science Frontiers Sourcebook Project Reviewed in:

Quotes

  • "A sourcebook of unexplained phenomena is therefore a valuable addition to a collection of scientific literature. William R. Corliss has provided this in the past with his source books of scientific anomalies in several subjects, and now he has provided it for astronomy. He has done an excellent job of collecting and editing a large amount of material, taken in part from scientific journals and in part from scientific reporting in the popular or semi-scientific press." -- "The Mysterious Universe: A Handbook of Astronomical Anomalies", reviwed by Thomas Gold, Cornell University, in Icarus, vol.41, 1980

  • "An interesting, systematic presentation of unusual weather [..] This book is recommended for a general audience" --"Corliss, William R., Tornados, Dark Days, Anomalous Precipitation, and Related Weather Phenomena, Sourcebook Project, 1983.", revieweed in Choice, September 1983
  • "..the science is necessarily somewhat speculative, but Corliss's symthesis is based on reputable sources." -- "Corliss, William R. (Compiler). Lightning, Auroras, Nocturnal Lights, and Related Luminous Phenomena" reviwed by Joseph M. Moran, Univ. of Wisconsin in Science Books and Films, Sep/Oct 1983

  • "Before opening the book, I set certain standards that a volume which treads into dangerous grounds grounds like this must meet. The author scrupulously met, or even exceeded those standards. Each phenomenon is exhaustively documented, with references to scientific journals [..] and extensive quotations" -- "Book Review: The moon and planets: a catalog of astronomical anomalies", The Sourcebook Project, 1985., Corliss, W. R., Journal of the Royal Astronomical Society of Canada, Vol. 81, no. 1 (1987), p. 24., 02/1987