Figure 2. The −196.15 °C Steady-State Emission Spectra of PS-I.

(A) The solution spectrum of PS-I shows characteristic far-red fluorescence at the approximately 735-nm region, while dried PS-I shows a peak at approximately 683 nm.

(B) Emission spectra of samples containing DM retained partially their far-red fluorescence, but still showed a significant increase in fluorescence at approximately 683 nm. Additionally, the far-red fluorescence demonstrated a significant blueshift.

(C) Comparable changes are evident in the spectra of samples containing OG as seen in DM (B).