  The electronic structure including energy bands, band weights, and local
density of states (LDOS) of interfaces between hexagonal (AB) and rhombohedral
(ABC) graphite has been has been calculated. The full-potential local-orbital
code (FPLO) and the generalized gradient approximation (GGA) to the density
functional theory has been used. Both of the two existing interface structures
host (localized) interface bands, which are located around the K-point in the
Brillouin zone, and which give rise to strong peaks in the LDOS at the Fermi
energy. All interface bands near the Fermi energy are localized at monomers
(single atoms with dangling $p_z$ bonds), whereas those around 0.5 eV belong to
$p_z$-bonded trimers, which are created by the the interface and which are not
found in the two adjacent bulk substances. There is also an interface band at
the (AB) side of the interface which resembles one of the interface states near
a stacking fault in (AB) graphite.
