[xcrysden] negative isovalue

[Tone Kokalj]

> Hello Tone,
>
> Thank you for a great software and for putting up this mailing list!

Thanks!

As for the mailing list, we should really thank Democritos
(http://www.democritos.it/) for hosting the mailing list.

> I have a question related to the meaning of the "isovalue" used in
> density plots.  I have molecular orbitals, calculated at gamma-point
> using PWSCF. I generated xsf files for |psi|^2 that preserve the sign,
> and in particular one of the orbitals have a maximal value of 0.000065
> and minimal value of -0.270350, i.e. a negative sign of the orbital.
>
> When I specify isovalue of -0.001, would it enclose the negative part of
> the density (rho<-0.001) or the positive part (rho>-0.001)? (I hope I
> made myself clear).

If I undesrtand you right, than you want to plot the isosurface:
in this case the isovalue of -0.001 will plot the isosurface with that
particular value.

I've never used the sign option of the PWscf, but I guess in this case the
sign() * |psi|^2 is written on the file, so the above stated holds.

Regards, Tone