if the quinone electron acceptor ( q ) is in the oxidized state , flash excitation generates a transient state ( pf ) , in which an electron has moved from the primary electron donor ( p , a dimer of bacteriochlorophylls ) to an acceptor complex involving a special bacteriopheophytin ( h ) and another bacteriochlorophyll ( b ) .
C0600166
a
C0004638
bacteriochlorophyll