Quantum chemical approach to atomic manipulation of chlorobenzene on the Si(111)-7 × 7 surface: Resonance localization, vibrational activation, and surface dynamics
نویسندگان
چکیده
We present a cluster model to describe the localization of hot charge carriers on the Si(111)-7 × 7 surface, which leads to (nonlocal) desorption of chlorobenzene molecules in scanning tunneling microscope (STM) manipulation experiments. The localized charge carriers are modeled by a small cluster. By means of quantum chemical calculations, this cluster model explains many experimental findings from STM manipulation. We show that the negative charge is mainly localized in the surface, while the positive one also resides on the molecule. Both resonances boost desorption: In the negative resonance the adatom is elevated; in the positive one the chemisorption bond between the silicon surface adatom and chlorobenzene is broken. We find normal modes promoting desorption matching experimental low-temperature activation energies for electronand hole-induced desorption.
منابع مشابه
Nonlocal desorption of chlorobenzene molecules from the Si(111)-(7×7) surface by charge injection from the tip of a scanning tunneling microscope: remote control of atomic manipulation.
We report the nonlocal desorption of chlorobenzene molecules from the Si(111)-(7×7) surface by charge injection from the laterally distant tip of a scanning tunneling microscope and demonstrate remote control of the manipulation process by precise selection of the atomic site for injection. Nonlocal desorption decays exponentially as a function of radial distance (decay length ∼100 A) from the...
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