You can visualize it by VESTA

Dear Ding 

To be precise i am talking about contour plot of frontier KS orbitals for molecule adsorbed on solid surface. As far as I know VESTA allows one to vizualize crystal structure, charge and spin density distribution, local potential etc. The information which interests me is stored in WAVECAR file but i don't know how to extract necessary data from it in order to draw the contour plot of LUMO and HOMO.

The answer would still be VESTA ;-). However, you will not use the standard CHGCAR, you will generate a band-decomposed charge-density. This is a post processing calculation starting from the wavecar which generates the electron density due to a specific band(-range) at a specific k-point(-set) or an energy-range at a specific k-point(-set).

From your DOS/bandstructure you know where to find the bands/energy-range you are interested in. (this is quite easy to do and physically sensible)

You can however also transform the wavefunction into maximally localized warnier-orbitals and visualize those.(but that is quite a bit trickier and more difficult...and the physics may not be as clear as well) 

I discuss how to get band-projected charge density (PARCHG) files from VASP in my dissertation, linked here (see in particular the discussions on WAVECAR and CHGCAR on pages 299-301, and example band-projected charge density maps on page 188). See also the VASP manual page linked below.

To plot charge densities for a particular band (in your case, the HOMO or LUMO) using VESTA software, I think you just need to change the name of the PARCHG output file to CHGCAR and then open that file in VESTA. Details on how to modify the image by adjusting isosurface values, visualization type, etc. can be found in the VESTA manual, also linked here.

http://jp-minerals.org/vesta/en/doc.html

http://cms.mpi.univie.ac.at/vasp/guide/node145.html

Research Atomic Scale Structure-Chemistry Relationships at Oxide Cata...

Danny and Martin, thank you very much for  thorough suggestions ! Martin, thank you very much for the link to your PhD thesis as well. Coincidentally my question concerns DFT investigation of AuPd supported TiO2 for photocatalytic oxydation reaction. So i gotta take a look on it later on. Well, coming back to the question posted, the band-projected charge density can be a good idea to capture ( at least approximate shape HOMO ) but... what if we wanna visualize LUMO (where in the ground state charge density is basically zero) ? 

If you have a bit of charge density above the Fermi level (thanks to smearing) which corresponds to the LUMO, you should be able to visualize that density. I don't know how accurately that would represent your LUMO, though. You may need to use excited-state methods (with which I am not very familiar).

I think from the PARCHG file we get the shape of the orbital. However when I opened it in VESTA I couldn't observ the phase of the orbitals. Can anyone suggest me how to look at the phase of the orbitals?

Dear Dr. Martin E. McBriarty,

Please link your dissertation as you wrote in your previous post about band-projected charge density (PARCHG). I am also interested.

Thank You

Shilendra

Shilendra, the publication is attached to my previous comment when I edit it, but it isn't showing up in the published answer. Must be an issue with RG. Here's a link: https://www.researchgate.net/publication/279174293_Atomic_Scale_Structure-Chemistry_Relationships_at_Oxide_Catalyst_Surfaces_and_Interfaces

Research Atomic Scale Structure-Chemistry Relationships at Oxide Cata...

The phase of the orbital is associated with the sign of the corresponding wavefunction. By looking at the phase (negative or positive) You can deduce whether the orbital is symmetric or assymertic with respect to the given point group. The PARCHG file provides essentialy the charge density projected onto the selected band (orbital). In fact, it gives you an idea about the approximate shape of the orbital but not about the phase. The second limitation of PARCHG is that, in principle, you are not capable of drawing the antibonding orbitals (above the Fermi level), where the charge density approaches zero.