Environmental Engineering Reference
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Figure 5.3 Cross-section of SiNWs with different surface nitrogenation
ratio: (a) 0%; (b) 14%; (c) 29%; (d) 43%; and (e) 50%. Here silicon,
hydrogen, and nitrogen atoms are displayed by yellow, green, and blue
balls, respectively. The cross-sectional area is 2.36 nm 2 . Reprinted with
permission from [43].Copyright c
2012, City University of Hong Kong.
different numbers of nitrogen atoms. Here surface nitrogenation
ratio denotes the ratio of the number of nitrogen atoms in N-SiNW
to the numberofsurface Si atoms in H-SiNW.
5.2.2 Green-Kubo MD Method
EMD simulation has emerged as a powerful tool for predicting the
lattice thermal conductivity in nanomaterials [10-13]. One major
advantage of this method is that it does not rely on too many
approximations and assumptions of the detailed phonon processes,
which are necessities in solution of Boltzmann transport equation
[11]. In MD simulations, interaction between atoms is described
by Tersoff potential [47] that changes chemical bond strength
according to the localcoordination environment[28],
V ij =
f C ( r ij )[ f R ( r ij ) + B ij f A ( r ij )],
(5.1)
where f C is a smooth cut-off function, f A and f R are attractive
and repulsive pair potential functions, and the bond-order term
 
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