Resonance vs. Resonation

[Some of this is just rationalization, and some speculation, as the word 'Resonation' does not appear to exist in all dictionaries]

A 'Resonation' (noun) is an individual instance of the action (verb) 'Resonate' (or, in combination with the verb 'to be', e.g., 'is Resonating', or 'will Resonate').

'Resonance' (noun) could also be used to substitute for 'Resonation' (and is probably a far more commonly used word).

However, 'Resonance' also refers to a property (e.g., having 'Resonance' is having the ability to 'Resonate'), or as a modifier (e.g., 'Resonance frequency'), whereas 'Resonation' would more be properly used as a noun of single instance of 'Resonance' or 'Resonating'.

So, I can see 'Resonation' used as a more technical, or specific term.

Examples:

1.) The last resonation of the C4 note, as performed by the lead singer of the band, was particularly powerful.

2.) When the next resonation of the oscillator circuit occurs, notate the (resonance) frequency in hertz.

Resonation is a technical term related to voice production. https://books.google.co.uk/books?id=GVeGnVinMa0C&pg=PA271&dq=%22resonation%22&hl=en&sa=X&ei=G7OZVZKGMMXxUq_QgYgH&ved=0CCoQ6AEwAg#v=onepage&q=%22resonation%22&f=false