No end of commotion having charged particle melting (6)
I believe the answer is:
fusion
'melting' is the definition.
(thesaurus)
'no end of commotion having charged particle' is the wordplay.
'no end of' means to remove the last letter.
'commotion' becomes 'fuss' (fuss is a kind of commotion).
'having' means one lot of letters go next to another.
'charged particle' becomes 'ion' (I've seen this in another clue).
'fuss' with its final letter taken away is 'fus'.
'fus'+'ion'='FUSION'
(Other definitions for fusion that I've seen before include "Process of melting to join two or more into one" , "Blend" , "Act of joining as one" , "The blending of different things into a whole" , "This kind of music" .)