caculate work-function of cnt(carbon nanotube) need dipole correction?

[baoailin]

hi:
we know we could use IDIPOL=1-3 for slab caculation,and use IDIPOL=4 for isolated molecules.However,how to set this parameter when caculate work function of cnt.
1)should I only need to add LVTOT = .TRUE. in the INCAR?2) the Fermi energy changes with ionic relaxation,how to conform this value,should I sum fermi energy of every ionic step and divides number of steps,or just regard the last step as the fermi energy that we want to get.
3)how to plot graph of work function of cnt.
Thanks

[admin]

1) Dipole corrections are only needed if the cell / molecule has a net dipole moment. check if this is the case for your cell
2) it only makes sense to give the fermi energy for the completely relaxed (also geometrically!) structure.
3) the work function is a single number.