One possible elementary form of love inspired by delirious poet after Alison's heart (7)
I believe the answer is:
isotope
'one possible elementary form' is the definition.
(form of a chemical element)
'delirious poet after alison's heart' is the wordplay.
'delirious' indicates an anagram.
'after' is a charade indicator (letters next to each other).
'heart' indicates the central letters.
The middle of 'alisons' is 'iso'.
'poet' anagrammed gives 'tope'.
'tope' after 'iso' is 'ISOTOPE'.
'of love inspired by' is the link.
This may not be right. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for isotope that I've seen before include "O, is poet involved in chemical element?" , "Type of atom, maybe radioactive" , "O, is poet a species of atom?" , "Variant of a particular chemical element -- ie stoop (anag)" , "Atomic stuff" .)