Leng et al. reply

Conwell, Rothberg, and Mizes (CRM) claim [1] that, as a result of chain length distribution and vibronic sidebands of electronic levels in PPV films, there is little correlation between increase of pump photon energy (Hw) and increase of electronic energy, and therefore data from excitation spectroscopies such as those given in [2] cannot be used to study the electronic band structure of the polymers. Short chains and vibronic side band effects certainly broaden sharp spectroscopic features [3], but we disagree that these effects obscure spectroscopic data in "real samples."