Formation mechanism of CCl 4− anion in condensed phase: a direct ab initio dynamics study

Abstract

The structures and electronic states of the CCl 4 − anion in the condensed phase have been studied by direct ab initio dynamics calculation. The calculation showed that two stationary points were obtained as stable forms of CCl 4 −, which correspond to elongated and compressed forms of CCl 4 −. The elongated form has an elongated C–Cl bond, whereas the compressed form has a shorter C–Cl bond in CCl 4 −. The MP4SDQ/6-31G∗ calculation indicated that the elongated form is energetically more favored than the compressed form. However, the contact spin density for the elongated form disagrees with that measured by electron spin resonance spectroscopy in the condensed phase. By contrast, the spin density for the compressed form is in reasonable agreement with the experiment. The formation mechanism of the compressed form in the condensed phase is discussed on the basis of direct ab initio dynamics calculation. The present results strongly indicated that the CCl 4 − has the compressed form in condensed form.