Motivated by the various physical properties observed in
θ-(BEDT-TTF)2​X, we study the ground state of extended Hubbard model
on two-dimensional anisotropic triangular lattice at 1/4-filling with
variational Monte Carlo method. It is shown that the nearest-neighbor Coulomb
interaction enhances the charge fluctuation and it induces the anomalous state
such as charge-ordered metallic state and the triplet next-nearest-neighbor
f-wave superconductivity. We discuss the relation to the real materials and
propose the unified view of the family of θ-(BEDT-TTF)2​X.Comment: 4 pages, 5 figure