Two-dimensional Weyl points and nodal lines in pentagonal materials and their optical response

Two-dimensional pentagonal structures based on the Cairo tiling are basis of a family layered materials with appealing physical properties. In this work we present theoretical study symmetry-based electronic and optical properties these materials. We provide complete classification space groups that support for binary ternary systems. By means first-principles calculations, their band local spin textures in momentum analyzed. Our results show can be realized chiral achiral lattices Weyl nodes pinned at high-symmetry points nodal lines along Brillouin zone boundary; degeneracies protected by combined action crystalline time-reversal symmetries. Additionally, discuss linear nonlinear features some penta-materials, such as shift current, which shows an enhancement due to presence points, possible applications.