adsorption energy is too high when using optb88 correction
Posted: Mon Feb 10, 2020 3:16 pm
Hello all,
when I use opt88 vdwcorrection to calculate 3 layers 12*12 Ag(111) slab with a 18 A vacuum layer , the total energy is positive
and this lead to a large adsorption energy.
however when I use PBE without any correction, the adsorpiton energy is small and resonable.
could anyone tell me why?
Thanks a lot
when I use opt88 vdwcorrection to calculate 3 layers 12*12 Ag(111) slab with a 18 A vacuum layer , the total energy is positive
and this lead to a large adsorption energy.
however when I use PBE without any correction, the adsorpiton energy is small and resonable.
could anyone tell me why?
Thanks a lot