Approximate ab initio calculation of vibrational properties of hydrogenated amorphous silicon with inner voids
نویسندگان
چکیده
We have performed an approximate ab initio calculation of vibrational properties of hydrogenated amorphous silicon (a-Si:H) using a molecular dynamics method. A 216-atom model for pure amorphous silicon (a-Si) has been employed as a starting point for our a-Si:H models with voids that were made by removing a cluster of silicon atoms out of the bulk and terminating the resulting dangling bonds with hydrogens. Our calculation shows that the presence of voids leads to localized low-energy (30–50 cm) states in the vibrational spectrum of the system. The nature and localization properties of these states are analyzed by various visualization techniques. @S0163-1829~98!02647-2#
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