Proposed structure of carbon clusters queried

Abstract

A bit of controversy has swirled up between two research groups investigating carbon clusters in molecular beams. Chemists at Exxon Research & Engineering Co., Annandale, N.J., are suggesting that chemists at Rice University have drawn unwarranted conclusions about the structure of such clusters from photoionization data. The debate centers on recent research by Richard E. Smalley, who is Hackerman Professor of Chemistry at Rice, and coworkers. Last year, Smalley reported that laser vaporization of graphite under the proper conditions gave rise to two extremely stable carbon clusters, C 60 and C 70 . The stability of the C 60 cluster led to the suggestion by the Rice chemists that it was a spherical molecule with the geometry of a truncated icosahedron (C&EN, Dec. 23,1985, page 20.) The researchers also discovered that vaporization of graphite impregnated with lanthanum trichloride produced very stable complexes containing an even number of carbon atoms ranging from 44 to 76 and a single lanthanum atom. ...