slides (pdf)

How To Find Migration Barriers II
New reliable search methods for diffusion paths exist like:
• Nudged elastic band method” (Jónsson et al.). Used in this work.
• Dimer method (Henkelman et al.)
• MD (usually too slow); but can do “accelerated” MD (Voter)
• All in VASP, easy to use.
a b c
Initial Saddle Final
Elastic band method:
Minimize energy of all snapshots plus
spring terms, E chain :
E
E
chain
spring
ab
=
=
all atoms
b c
spring
ab
1
k j j
2
Computational Materials Science and Engineering
E
a
+
∑
E
2
+ E
+ E
+
E
spring
bc
( a b
x − x ) ( Hooke' s Law )