Crossed-beam studies of electron transfer to oriented trichloronitromethane, CCl(3)NO(2), molecules.

Fast potassium atoms donate an electron to CCl(3)NO(2) molecules to form K(+) ions and the negative ions O(-), Cl(-), NO(2) (-), CCl(3) (-), CCl(2)NO(2) (-), CCl(3)NO(-), and CCl(3)NO(2) (-). Threshold energies are measured for these ions and electron affinities for CCl(2)NO(2) (-), CCl(3)NO(-), and CCl(3)NO(2) (-) are estimated to be 2.35, 2.35, and 1.89 eV (+/-0.6 eV), respectively. The threshold energies show that the C-N and N-O bonds are substantially weaker than in nitromethane. The CCl(3)NO(2) molecules are oriented before the collision and at energies near 2.5 eV the electron appears to transfer to the pi( *) (NO) orbital forming the parent negative ion, CCl(3)NO(2) (-), which is stabilized by interacting with the K(+) donor. As the collision energy increases the parent negative ion fragments and the orientation dependence of the fragment ions helps understand the fragmentation pathway.