In the systemlabel.EIG file are all the eigenvalues of the Kohn-Sham Electron-System listed, together with the Fermi-Level (E_F), located at the first row of the file. The energy-value below E_F represents the HOMO, the energy-value above E_F the LUMO level. So all you have to do is locate those two energy levels in the *.EIG file, and determine their position. If the HOMO is the 56th eigenvalue, LUMO the 57th eigenvalue, then you have to create the orbitals with denchar for wavefunction number 56 and 57.
Assuming you used Denchar correctly, using a software like VMD you can load the systemlabel.K1.W56.MOD.cube file (*.REAL.cube if you care about the sign) and visualize the HOMO (*.57.MOD.cube for LUMO). In the Graphical Representation window of VMD you change following: Drawing Method 'Isosurface' Isovalue '0.05' or something else Draw 'Solid Surface' Show 'Isosurface' You can also use XCrySDen: http://www.home.uni-osnabrueck.de/apostnik/Lectures/SIESTA-visual.pdf Best wishes, Frank > Hello everyone I have run siesta and denchar and got a lot of *.cube > files. If I > want to obtain LUMO and HOMO,what should I do next ? > which software should I use ? > I am looking forward your reply! > Thanks in advance! > hamidreza balangi >
