No, but first I take in atmosphere in an African capital (7)
I believe the answer is:
nairobi
'an african capital' is the definition.
(capital of Kenya)
'no but first i take in atmosphere' is the wordplay.
'but first' becomes 'b' (1st letter of 'but').
'take in' means one lot of letters goes inside another.
'atmosphere' becomes 'air' (synonyms).
'no'+'b'+'i'='nobi'
'nobi' placed around 'air' is 'NAIROBI'.
'in' acts as a link.
(Other definitions for nairobi that I've seen before include "African city" , "Kenyan city" , "East African capital" , "Kenyan capital" , "Kenya's capital city" .)