  In this work, we predict a novel band structure for Carbon-Lithium(C4Li)
compound using the first-principles method. We show that it exhibits two Dirac
points near the Fermi level; one located at W point originating from the
nonsymmophic symmetry of the compound, and the other one behaves like a type-II
Dirac cone with higher anisotropy along the {\Gamma} to X line. The obtained
Fermi surface sheets of the hole-pocket and the electron-pocket near the
type-II Dirac cone are separated from each other, and they would touch each
other when the Fermi level is doped to cross the type-II Dirac cone. The
evolution of Fermi surface with doping is also discussed. The bands crossing
from T to W make a line-node at the intersection of kx={\pi} and ky={\pi}
mirror planes. The C4Li is a novel material with both nonsymmorphic protected
Dirac cone and type-II Dirac cone near the Fermi level which may exhibit
exceptional topological property for electronic applications.

Materials Science