title: Perchloropyracylene and its fusion with C60 by chlorine-assisted radio-frequency furnace synthesis.
abstract: Elusive perchloropyracylene has been obtained during conventional fullerene synthesis in a chlorine-containing atmosphere by using the radio-frequency furnace technique. In contrast to its hydrocarbon analogue, the title compound was found to be unexpectedly stable. Although the high stability of perchloropyracylene impedes its direct addition to C(60) fullerene, the corresponding adduct was found in the synthesis products extracted from the raw soot. Both new species were separated and unambiguously characterized by single-crystal X-ray analysis. According to experimental observations and quantum chemical calculations, the addition of perchloropyracylene to the C(60) fullerene can only be realized by involving highly reactive species such as C(14) clusters displaying the pyracylene connectivity. Such a viable mechanism includes capturing of free or partially chlorinated C(14) clusters with pyracylene-type connectivity by the fullerene molecule and subsequent stabilization through chlorine addition. The data obtained provide experimental evidence for the presence of pyracylene-like C(14) clusters in the gas phase, which have evolved during the graphite vaporization process. According to the pentagon road mechanism, such clusters are regarded as crucial intermediates in fullerene formation.
authors: Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors: Andreas
authors: A
authors: Mueller
authors: Karolin
authors: K
authors: Ziegler
authors: Konstantin Yu
authors: KY
authors: Amsharov
authors: Martin
authors: M
authors: Jansen