Excited state coherent vibrational motion in deoxymyoglobin

Femtosecond coherence spectroscopy of deoxymyoglobin has been performed und er excitation in the lowest electronic transition (Q band) and probing in t he Soret band. Under these excitation conditions, ground state low-frequenc y vibrational motions are strongly suppressed with respect to Soret excitat ion. Evidence is presented for a contribution of excited state vibrational dynamics to the coherent response.