compute voronoi/atom returning all 1's


I’m studying damage cascades in FCC Ni-Fe-Cr. I’m trying to calculate vacancy and interstitial distributions using the “compute voronoi/atom occupation” command. Below is part of my code (showing only commands related to voronoi calculation)

After creating perfect FCC lattice

compute compute3 all voronoi/atom occupation

Initialize velocity at 800 C

Equilibrate for 2 ps

Set velocity PKA in the center = 10 keV

Initial phase

timestep 0.00001
dump dump4 allatoms custom 100 10_100_2_init.voronoi type id c_compute3[1] c_compute3[2]
run 20000
undump dump4

I was able to successfully visualize vacancy and interstitial cascades using OVITO’s Wigner-Seitz defect analysis tool. But my output file for the voronoi data contains two columns of “1” only, which means that all the atoms are in the original voronoi cells as defined with the perfect lattice.

Why am I seeing only columns of 1’s? I was expecting 0’s for vacancies and >1 for interstitials.



I agree that you should see some 2’s and 0’s. I just generated a dump file for TEST_5 of examples/in.voronoi and got the expect output:

999 1 9.75 4.25 2.75 1 1
13 2 4.45 6.45 0.45 0 2
257 2 4.25 6.25 0.25 2 2

So there must be something wrong with how you are doings things, or maybe the interstitials are forming in a way that does not change the occupancy in the way that you expect.