Reactivities of titanium metallo-carbohedrene Ti8C12+ at thermal energies

Abstract

Reactivities of the Met-Car Ti[sub 8]C[sub 12][sup +] toward various molecules have been examined at thermal energies employing a selected drift tube reactor coupled with a laser induced plasma source. It is observed that this cluster is quite reactive toward molecules with either large dipole moments or [pi]-bonding systems. At room temperature Ti[sub 8]C[sub 12][sup +] is found to take up 8 polar molecules but only 4 molecules with [pi]-bonding systems. The Met-Car cluster ion reactions are observed to proceed mainly through association mechanisms leading to ligand attachment rather than those involving breaking and forming of new chemical bonds. In addition, Ti[sub 8]C[sub 12][sup +] is seen to be inert even toward oxygen, which is known to be a good free radical scavenger. The association or attachment behavior of Ti[sub 8]C[sub 12][sup +] reactions is explained in terms of a closed structure of the Met-Car and the presence of titaniums in the framework of Ti[sub 8]C[sub 12][sup +]. Hence, the observed reactivities of Ti[sub 8]C[sub 12][sup +] provide further suggestive evidence supporting the argument that the Met-Car Ti[sub 8]C[sub 12] has a dodecahedral structure. 23 refs., 3 figs.