CCL:G: locate the transition state of E/Z isomerization of 2-butene using DFT



Hi, 

 

It is indicated in literature that the transition state of E/Z isomerization of 2-butene is a bi-radical state with 90 degree of twist along the central C-C bond.  However, I could not locate the transition state using DFT based method implemented in Gaussian.  I have tried restricted and unrestricted singlet state, starting from various geometries, using “scan” key words, using QST3 method...

 

Will you provide any suggestion?

 

Thanks,

 

Jun