Accurate Bulk Properties from Approximate Many-Body Techniques

For ab initio electronic structure calculations, the random-phase approximation to the correlation energy is supposed to be a suitable complement to the exact exchange energy. We show that lattice constants, atomization energies of solids, and adsorption energies on metal surfaces evaluated using this approximation are in very good agreement with experiment. Since the method is fairly efficient and handles ionic, metallic, and van der Waals bonded systems equally well, it is a very promising choice to improve upon density functional theory calculations, without resorting to more demanding diffusion Monte Carlo or quantum chemical methods.

Figure 1

Relative error (%) of the theoretical lattice constants of insulators, semiconductors, and metals. The experimental lattice constants are summarized in Ref. 33 and have not been corrected for zero-point vibrational effects.

Figure 2

Atomization energies ($\mathrm{eV}/\mathrm{\text{atom}}$) evaluated from EXX and RPA, compared to experimental and DFT-PBE values.

Figure 3

RPA atomization energy ($\mathrm{eV}/\mathrm{\text{atom}}$) of diamond and graphite versus $\mathrm{\text{volume}}/\mathrm{\text{atom}}$. The experimental equilibrium volumes and atomization energies are indicated by black diamonds and black triangles. The experimental values are shifted upwards by 0.3 eV. The inset shows the RPA correlation energy of graphite versus $1/d^4$, where $d$ is the graphite interlayer distance.