Hi Frederico, About macroave, the first column refers to the z coordinates axis and the second column refers to the value of the potential (planar average or macroscopic average)?
I used the input(macroave-surface.in) of example folder. If it that I wrote above is correct, then should I look to the second column and see if the values are constant at region of the electrode and the interface? Comparing the bias cases of 0.0 and 0.3, I note that the values of the case 0.0 is more constant than case 0.3(sometimes, varies of 0.4 between two consecutive points ). Therefore, I must add more unit cell layers of GNR in the scattering region? About the contour option, I increased the value to 30,but the convergence was not reached. About your "PS", I didn't understand. My electrode is shaped by 3 unit cell of GNR. Do you mean that when i want to increase de ribbon lenght i can add only one unit cell? If is this, i know. I have included three whole layers in ribbon(which is the electrode), because I thought it could guarantee that the interface region would not suffer variation anymore, but I was wrong. There are any recommendation? I am open to new ideas. I want to thanks you Frederico, by your remarks. Yoshi > As you have already verified it is important to have a sufficient number > of electrode layers in the scattering region, and the reason is for > "things" to be sufficiently converged to bulk values in the electrodes' > regions (as you probably know). Now, as you apply higher biases, > depending on the screening properties of your material, you may need to > include even more electrode layers. You can use the .VH file and the > macroave program to see how the electrostatic potential is changing with > the applied voltage. The applied bias should be screened inside the > scattering region, resulting in an essentially constant (averaged) > potential outside of it. If this is not the case, then you will have to > include more GNR layers. > > As you seem to have a bias related problem, another thing to check are > your contour options, mainly the number of points in the bias window. > > Best regards, > > Frederico. > > PS - You don't need to add 42 atoms each time you want to add more > layers ... just to make sure. > >
