An ab initio MO Study of the Gas-Phase Reactions 2 SF2 → FS−SF3 → S=SF4 − Molecular Structures, Reaction Enthalpies and Activation Energies

✍ Scribed by Yana Steudel; Ralf Steudel; Ming Wah Wong; Dieter Lentz

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 123 KB
• Volume: 2001
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/1099-0682(200109)2001:10<2543::aid-ejic2543>3.0.co;2-6

✦ Synopsis

High level ab initio MO calculations at the G3(MP2) level of theory were employed to study the molecular structures of SF 2 , FSSF 3 , and SSF 4 , as well as the dimerization of gaseous SF 2 to FSSF 3 and the isomerization of FSSF 3 to SSF 4 . The dimerization of SF 2 was calculated to be an exothermic process (∆H°2 98 = -77 kJ•mol -1 ) with an activation enthalpy (∆H ϶ 298 ) of 65 kJ•mol -1 . The transition state of the dimerization reaction is characterized by a bridging fluorine atom that undergoes a 1,2-shift, and a weak sulfur-sulfur single bond. The calculated lowest-energy structure of FSSF 3 (2a) is in excellent agreement with the experimentally derived 2 SF 2 ǟ Ǟ FSϪSF 3 (1) [ ‡] Sulfur Compounds, 217.