The American Physical Society Acta Medica Okayama 1098-0121 82 19 2010 Electronic structure of pristine and K-doped solid picene: Nonrigid band change and its implication for electron-intramolecular-vibration interaction 195114-1 195114-5 EN H Okazaki T Wakita T Muro Y Kaji X Lee H Mitamura N Kawasaki Y Kubozono Y Yamanari T Kambe T Kato M Hirai Y Muraoka T Yokoya We use photoemission spectroscopy to study electronic structures of pristine and K-doped solid picene. The valence band spectrum of pristine picene consists of three main features with no state at the Fermi level (E_F) while that of K-doped picene has three structures similar to those of pristine picene with new states near E_F, consistent with the semiconductor-metal transition. The K-induced change cannot be explained with a simple rigid-band model of pristine picene but can be interpreted by molecular-orbital calculations considering electron-intramolecular-vibration interaction. Excellent agreement of the K-doped spectrum with the calculations points to importance of electron-intramolecular-vibration interaction in K-doped picene. No potential conflict of interest relevant to this article was reported.