How to calculate the excitonic optical properties in vasp?

Message

xfh00 · #1 Post by **xfh00** » Mon Jul 20, 2009 11:50 pm

Dear all,
Does VASP 4.6 can calculate the excitonic optical properties? How to perform? Many Thanks.
xfh00

panda · #2 Post by **panda** » Wed Jul 22, 2009 10:02 pm

no, this is implemented in version 5.2 though

xfh00 · #3 Post by **xfh00** » Fri Jul 24, 2009 11:34 pm

THANK YOU!

panda · #4 Post by **panda** » Mon Jul 27, 2009 4:37 am

No problem! I am going to try doing some calculations this week using the optical properties module. I started a thread for discussions on optical properties and GW calculations.

xfh00 · #5 Post by **xfh00** » Thu Jul 30, 2009 1:49 am

I have read PRL 100, 189701 (2008) PHYSICAL REVIEW B 75, 235102 2007, in which the GW have been studied by vasp(not 5.2).

xfh00 · #6 Post by **xfh00** » Thu Jul 30, 2009 1:49 am

I have read PRL 100, 189701 (2008) PHYSICAL REVIEW B 75, 235102 2007, in which the GW have been studied by vasp(not 5.2).

irene · #7 Post by **irene** » Thu Jul 30, 2009 9:25 am

How do you know Vasp 5.2 can calculate excitonic optical properties? Because I didn't find anything about this in the manual. It is in the list of new features but it is not reported further in the manual.
And what are the variables involved? How does it calculate the excitonic contribution?
Based only on the manual, it does not seem to do it... and if it does, it seems to be only on alpha stage and not reported...

panda · #8 Post by **panda** » Thu Jul 30, 2009 4:40 pm

I am basing on this: http://cms.mpi.univie.ac.at/vasp/vasp/n ... l#incar-lr
that it is available in 5.2 but not 4.6

irene · #9 Post by **irene** » Thu Jul 30, 2009 4:52 pm

Ok, but this is only RPA (LRPA=TRUE) or a simple sum over independent transitions (LOPTIC=TRUE, which was working also in vasp 4.6). No excitonic effects are taken into account in any of them.