average electrostatic potential

[zhr.adinehphd]

I want to calculate the band offset in the interface A/B.
for this purpose should calculate the average electrostatic potential.
Cell parameters are grown in the direction of the axis z.
Please tell me what option is included in the input file of abinit to calculate the average electrostatic potential ( ΔV)?
Is it correct to use prt1dm option?
And whether the prt1dm output file should be done averaging the direction of the axis z?
With warm regards.