Rearrangement processes of negative ions in the gas phase: [M Hal]− ions in halogenated azobenzenes. Resonance stabilization of negative ions

✍ Scribed by M. V. Muftakhov; Yu. V. Vasil'ev; V. A. Masunov; V. V. Takhistov; D. A. Ponomarev

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 666 KB
• Volume: 30
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/jms.1190300208

✦ Synopsis

Abstract

Ionization efficiency curves for [M  X]^−^ ions from p‐XC~6~H~4~NNC~6~H~5~ molecules (XF, Cl, Br) have been registered in the energy range 0–9 eV with appearance energies 3.3, 4.1 and 3.2 ± 0.2 eV, respectively. The heats of formation of 17 isomeric C~12~H~9~N^−^ ions have been estimated using isodesmic reactions. The possible mechanism of isomerization of molecule ions leading to various isomeric [M  X]^−^ ions is represented. The resonance stabilization of both negative and positive ions, questioned for negative ions by some workers, was confirmed by measuring appearance energies of conjugated ions [M  H]^−^ and [M  (CCl~2~ + CI)]^−^ or [M  Me]^+^ and [M  CCl~3~]^+^ coming from p‐MeC~6~H~4~OR (R or Me) and 4‐Methyl‐4‐trichloromethylcyclohexa‐2,5‐dienone, respectively.