Metallic Car–Parrinello Dynamics

Abstract

We have implemented a new Car–Parrinello dynamics for metallic systems. In this scheme, including fractional occupations of Kohn–Sham orbitals, the dynamical variables representing electronic wave functions are extended to two kinds of freedom, the conventional fictitious variables and the variables related with the unitary transformation among the orbitals. The applications to liquid Si and Al yielded the satisfactory results, compared with the previous works. The trajectory of electronic freedoms was shown to always evolve just above the Born–Oppenheimer surfaces.