Weak ion-molecule complexes of F−(CF4)n and CF3−(CF4)n

✍ Scribed by Kenzo Hiraoka; Masayuki Nasu; Susumu Fujimaki; Edgar W. Ignacio; Shinichi Yamabe

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 329 KB
• Volume: 245
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(95)00980-i

✦ Synopsis

Gas-phase thermochemical stabilities and structures of cluster ions F-(CF4) n and CF~-(CF4) ~ have been studied with a high-pressure mass spectrometer and ab initio calculations. The F-... CF a bonding energy is found to be only 6.4 kcal/mol. Its geometry is of an ion-dipole complex along an Sr~2 reaction path. The high-symmetry (D3h) CF~ species is computed to be a transition state of the SN2 path and not an energy minimum. The CF~-... CF4 bonding energy is only 3.6 kcal/mol with F2C-F-... CF a coordination. The F... F exchange repulsion hinders the F... C attractions in these species. Theoretical bonding energies are in good agreement with measured ones.