A Near-Infrared Transient Absorption Study of the Excited-State Dynamics of the Carotenoid Spirilloxanthin in Solution and in the LH1 Complex of Rhodospirillum rubrum.
The spectroscopic properties of spirilloxanthin in an nhexane solution and bound to the core light-harvesting LH1) complex of Rhodospirillum rubrum were studied by near infrared ultrafast transient absorption spectroscopy. Global analysis of the kinetic traces measured after excitation of spirilloxanthin to the S2 (1Bu +) state enabled us to estimate the species-associated difference spectra that