14+ Transition States Organic Chemistry Montgomery (Selma) AL. Williams, in advances in physical organic chemistry, 2019. You may recall from general chemistry that it is often the transition state is an 'activated complex':

Hammond's Postulate - Chemwiki
Hammond's Postulate - Chemwiki from chemwiki.ucdavis.edu
Baker's transition state (ts) locating algorithm was incorporated into the density functional (df) program demon. Bridging theory and experiment in establishing the mechanisms. Hehre, w.j., lathan, w.a., ditchfield, r., newton, m.d., and pople, j.a., quantum chemistry program exchange, n°236, indiana university, bloomington, indianagoogle scholar.

The transition state of a chemical reaction is a particular configuration along the reaction coordinate.

I'm having trouble interpreting this image it will be your choice as to which will be the acid and base provided you pick consistently. Since a transition state exists at an energy peak, it is highly unstable and cannot be isolated. You may recall from general chemistry that it is often the transition state is an 'activated complex': However, in all the chemistry of the transition elements, the 4s orbital behaves as the outermost, highest energy orbital.