Electronic resonance with anticorrelated pigment vibrations drives photosynthetic energy transfer outside the adiabatic framework

The delocalized, anticorrelated component of pigment vibrations can drive nonadiabatic electronic energy transfer in photosynthetic light-harvesting antennas. In femtosecond experiments, this energy transfer mechanism leads to excitation of delocalized, anticorrelated vibrational wavepackets on the ground electronic state that exhibit not only 2D spectroscopic signatures attributed to electronic coherence and oscillatory quantum energy transport but also a cross-peak asymmetry not previously explained by theory. A number of antennas have electronic energy gaps matching a pigment vibrational frequency with a small vibrational coordinate change on electronic excitation. Such photosynthetic energy transfer steps…

• NS
  National Science Foundation

  Awards: CHE-1112365, 1112365, CNS-0821794, 0821794
• NC
  National Center for Atmospheric Research

  Award: CNS-0821794
• UO
  University of Colorado Boulder

  Award: CNS-0821794
• UO
  University of Colorado Denver

  Award: CNS-0821794
• DO
  Division of Chemistry

  Award: CHE-1112365