electrons are “hot” and not in equilibrium. they do all ... · tutorial on plasma...

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Electrons are “hot” and not in equilibrium. They do all the initial work.. (ions are static in comparison)

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Electron energies at the “high energy tail” end are not just sufficient to result in homolytic bond cleavage to make radicals, but also to ionise.

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There will be lots of radicals in the bulk of plasma.

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There will also be others species, such as metastables, but these are not our focus.

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If ions only result from electron collisions (high energy tail) then there won’t be there in high (ion) density in the plasma.

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But in plasma ions can be formed by proton transfer reactions. The proton comes from water – which is desorbed from the walls of the (glass) vessel under the impact of ions – more on this in a moment

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Basically there are a lot of possible reactions that can occur in the plasma bulk. And based on numbers (ie densities) the important ones would be radical- neutral and radical-radical, if polymer growth occurred entirely in the plasma phase!

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And mass spectral studies of species arriving to surfaces support this view.

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