Sun to employ gripping writers, to create tension (8)
I believe the answer is:
suspense
'tension' is the definition.
(thesaurus)
'sun to employ gripping writers' is the wordplay.
'sun' becomes 's'.
'to employ' becomes 'use' ('use' can be a synonym of 'employ').
'gripping' indicates putting letters inside.
'writers' becomes 'pens' (I've seen this before).
'use' placed around 'pens' is 'uspense'.
's'+'uspense'='SUSPENSE'
'to create' is the link.
(Other definitions for suspense that I've seen before include "Alfred Hitchcock was the master of it" , "State of nervous or excited tension or uncertainty" , "Uncertain state" , "Nervous anticipation" , "Feeling of excitement or anxiety about what might happen" .)