Carbon Tunneling from a Single Quantum State

  title={Carbon Tunneling from a Single Quantum State},
  author={Peter S. Zuev and Robert S. Sheridan and Titus V. Albu and Donald G. Truhlar and David A. Hrovat and Weston Thatcher Borden},
  pages={867 - 870}
We observed ring expansion of 1-methylcyclobutylfluorocarbene at 8 kelvin, a reaction that involves carbon tunneling. The measured rate constants were 4.0 × 10−6 per second in nitrogen and 4 × 10−5 per second in argon. Calculations indicated that at this temperature the reaction proceeds from a single quantum state of the reactant so that the computed rate constant has achieved a temperature-independent limit. According to calculations, the tunneling contribution to the rate is 152 orders of… 
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