Novel structures continue to be a mainstay of inorganic chemistry research. For example, the first thermally stable, crystalline trisilaallene derivative (shown) containing a formally sp-hybridized silicon atom was synthesized by chemistry professor Mitsuo Kira and coworkers at Tohoku University, Sendai [Nature, 421, 725 (2003)]. The Si5Si5Si skeleton is bent (with a bond angle of about 136°) and remarkably fluxional, in contrast to the rigid linear framework of carbon allenes. Such trisilaallene derivatives could be useful as synthetic reagents and building blocks for functional materials.
A novel metal dinitrogen complex, (C5Me5)3U(N2), is "the first monometallic f element complex of N2 of any kind," according to William J. Evans and coworkers at the University of California, Irvine [J. Am. Chem. Soc., 125, 14264 (2003)]. The work could lead to insights into f element coordination chemistry and nitrogen fixation.
Alexander I. Boldyrev of Utah State University, Lai-Sheng Wang of Washington State University and Pacific Northwest National Lab, and coworkers reported a Li3Al42 anion they prepared to be the first inorganic antiaromatic species ever identified [Science, 300, 622 (2003)]. However, some others believe that overall the species is aromatic, not antiaromatic [J. Am. Chem. Soc., 125, 13930 (2003)], and the issue is currently unresolved.