Quantum beats in the reaction center of Photosystem II

Abstract

Oscillations with a period of ∼ 400 fs and 1-2 ps have been observed upon excitation of the redmost absorbing pigments in the D1D2 cyt-b559 complex (RC) of Photosystem II. The 400 fs oscillations show no phaseshift and are therefore probably due to a quantum beat between two near-lying electronic levels, most likely two of the P680-multimer levels.