Site specificity in femtosecond laser desorption of neutral H atoms from graphite(0001).
نویسندگان
چکیده
Femtosecond laser excitation and density functional theory reveal site and vibrational state specificity in neutral atomic hydrogen desorption from graphite induced by multiple electronic transitions. Multimodal velocity distributions witness the participation of ortho and para pair states of chemisorbed hydrogen in the desorption process. Very slow velocities of 700 and 400 ms^{-1} for H and D atoms are associated with the desorption out of the highest vibrational state of a barrierless potential.
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ورودعنوان ژورنال:
- Physical review letters
دوره 104 25 شماره
صفحات -
تاریخ انتشار 2010