Communicate some grim particulars (6)
I believe the answer is:
impart
'communicate' is the definition.
(impart can mean to communicate or pass on)
'some grim particulars' is the wordplay.
'some' indicates the answer is hidden within the clue (some parts of the word are used).
'IMPART' is hidden within 'grim particulars'.
(Other definitions for impart that I've seen before include "Pass on information" , "Give - convey" , "Communicate (info)" , "Contribute" , "Pass on (knowledge, info)" .)