Propagation of a ballistic nuclear wavepacket on an adiabatic potential surface of a one-dimensional Br-bridged Pd complex without a self-trapped exciton state

摘要

The photoexcited state of one-dimensional Br-bridged Pd complex, which is a Peierls insulator, was studied using a femtosecond luminescence spectroscopy from near to mid-infrared region. The ultrafast decay with a time constant of 240±40 fs at all photon energies and delay of the maximum positions up to 160 fs with decreasing the photon energy were observed. These behaviors are ascribed to a slide down motion of the nuclear wavepacket on an adiabatic potential energy surface leading to the Mott-insulator domain without a local potential minimum corresponding to a self-trapped exciton.