April 2009 issue
Cover illustration: The structure of the 19-electron organometallic reducing agent decamethylcobaltocene, [bis-(pentamethylcyclopentadienyl)cobalt(II)], [Co(C10H15)2], fills a long-term gap in the literature. Recrystallization from a saturated hexamethyldisiloxane solution of the compound at 235 K finally provided crystals suitable for an X-ray structure determination and the structure is found to be isomorphous with decamethylferrocene and the low temperature polymorph of decamethylmanganocene. See Clark, Brennessel & Holland [Acta Cryst. (2009). E65, m391].