Hydrogen chloride, electronic states

The indicated electronic shift would result in a species (IV) containing a positively charged ortho position which would now accept the unshared pair of electrons from the attacking nucleophilic agent, the amine, to form the transition state (V). The latter finally eliminates one mole of hydrogen chloride with formation of the end product (VI) (Equation 3). 

As shown in Chapter X, the energy of a hydrogen chloride molecule in its normal electronic state can be approximately represented as... 

Figure 3-5 Approximate orbital description of the abstraction of a hydrogen atom by a chlorine atom to give a methyl radical and hydrogen chloride. Notice the rehybridization at carbon in the planar methyl radical. The additional three nonbonded electron pairs on chlorine have been omitted. The orbitals are not drawn to scale. The symbol 1 identifies the transition state.

So far we have not examined these polymers in detail but have obtained some preliminary data mostly on the DAF, benzidine and dlaminopyrene polymers. The former and the latter are blue, the other is dark grey, when in the neutral state. Solutions in DMF (N,N-dlmethyl -formamide) which are light brown, turn green upon acidification with hydrogen chloride. The electronic spectra of the as-formed DAF and benzidine polymers in solution revealed that they were essentially in the leuco form and that they could be Bronsted base doped. 

Activation methods can be divided into two groups. Activation by addition of selected metals (a few wt%), mainly transition metals, e.g., fine powders of Fe, Ni, Co, Cr, Pt, Pd, etc. ", or chlorides of these metals when these are reducible to the metal by hydrogen during presintering. The mechanism of activation is not understood (surface tension, surface diffusion, etc.) but is related to the electronic structure of the metal additive. Activation by carbon is also effective. Alternatively, activation utilizes powders in a specially activated state, e.g., very fine (submicronic) powders. ... 

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