DETERMINATION OF THE MOLECULAR STRUCTURE OF SEVERAL CARBO-CATIONS VIA THE ``COULOMB EXPLOSION'' TECHNIQUE

$^{1}$ E. P. Kanter, Z. Vager, G. Both, and D. Zajman, J. Chem. Phys. 85, 7487 (1986). $^{2}$ G. P. Raine and H. F. Schaefer, J. Chem. Phys. 81, 4034 (1984). $^{3}$ J. Pople, private communication.Author Institution: Argonne National Laboratory, 9700 S. Cass Ave.; Argonne National Laboratory, The Weizmann Institute of ScienceSeveral important carbo-cations such as $C_{2}H_{3}{^{+1}}$ and $CH_{5}^{+}$ have been studied by this radically new technique which obtains direct three-dimensional images of small molecules. Protonated acetylene has been a molecule of extreme interest because of the possibility of it assuming nonclassical ""bridged"" and classical ""nonbridged"" configurations. Our data is consistent with having the proton in the bridged position; the spatial geometry obtained is in quite reasonable agreement with ab $initio^{2,3}$ calculations. This work supported by the U. S. Department of Energy, Office of Basic Energy Sciences, under Contract W-31-109-ENG-38