Plotting exciton wavefunction
The exciton wavefunction can be written as [math]\displaystyle{ \psi_\lambda\left(r_e,r_h\right)=\sum_{vc} A_{vc}^\lambda \psi_v(r_h)\psi_c^*(r_e) }[/math] and depends on coordinates of a hole as well as an electron, thus two coordinates. In order to represent this function in 3D space we need to fix either the position of the electron $\psi_\lambda(r^*_e,r_h)$ or that of the hole $\psi_\lambda(r_e,r^*_h)$
Related tags and sections
CHGCAR, NBSEEIG, BSEHOLE, BSEELECTRON, BSE