ABINIT Discussion Forums

Hello,
i am computing finit electric filed for FeTiO3 in high pressure but i have an error. i put nband=16 but i get an error"in finit calculation nband have to be equel to valence bands" so when i change it to 50 but i have that error again. would you please tell me about my error?
Best regards.
Mina.

The finite field code requires that all bands be filled and no empty bands be present in the calculation. So you cannot have a metallic state, for example. You should able to compute the number of filled bands based on the number of valence electrons per atom and the number of atom in the unit cell. It may be that under pressure your system is going metallic (at least at the LDA level) and then the finite field calculation won't work (the theory is only for insulating states).