lelfield   LOGICAL
Default: .FALSE.  
If .TRUE. a homogeneous finite electric field described
through the modern theory of the polarization is applied.
This is different from "tefield=.true." !

efield REAL
Default: 0.D0  
Amplitude of the finite electric field (in Ry a.u.;
1 a.u. = 36.3609*10^10 V/m). Used only if lelfield=.TRUE.
and if k-points (K_POINTS card) are not automatic.

efield_cart(i), i=1,3 REAL
Default: (0.D0, 0.D0, 0.D0)  
Finite electric field (in Ry a.u.=36.3609*10^10 V/m) in
cartesian axis. Used only if lelfield=.TRUE. and if
k-points (K_POINTS card) are automatic.

Originally posted by souledge at 2011-05-16 15:57:04:
LZ不看软件的帮助文件是不对滴……

Originally posted by repent03 at 2011-05-16 17:19:24:
抱歉，我才接触没多久

导师忽然要我试试quantum-espresso

您提供的资讯是加电场的计算

我想问：像一个体系如果吸付了OH负离子

总电子数应该是体系电子数＋OH电子数+1

这个在VASP可透过NELECT来 ...

tot_charge         REAL
Default:         0.0

    total charge of the system. Useful for simulations with charged cells.
    By default the unit cell is assumed to be neutral (tot_charge=0).
    tot_charge=+1 means one electron missing from the system,
    tot_charge=-1 means one additional electron, and so on.

    In a periodic calculation a compensating jellium background is
    inserted to remove divergences if the cell is not neutral.