Datum:
Úterý, 5. Leden 2010 - 15:00 - 16:00
Místo konání:
Na Slovance, main lecture hall
Abstract:
We present first principles calculations of x-ray absorption spectra of
graphene and hexagonal BN monolayer on the Ni(111) substrate. Including
dynamical core-hole screening effects according to the theory of
Mahan--Nozieres--de Dominics (MND) results in an overall good
agreement
with the recent and new experimental data. This approach provides a
unified
first principles description of the electronic structure and core
excitations
in the
sp2-bonded materials on metal surfaces and a better insight into
the dynamics of screening effects. We demonstrate in particular that the
observed spectral features of graphene and hexagonal BN can be well
reproduced with the MND theory, and that they are determined by a delicate
balance between initial and final state effects.
