Full configuration interaction perspective on the homogeneous electron gas

Rank-Restricted Full Configuration Interaction

which is a linear combination of n-electron configurations, or determinants, with coefficients equal to c!. The components |Φ! form an orthonormal basis of the wavefunction. The determinants are the set of features that comprise the wavefunction, so we can optimize them by minimizing the electronic energy. To determine the energy of the wavefunction c, the Schrödinger equation in matrix form reads

Momentum distribution of the homogeneous electron gas.

We calculate the off-diagonal density matrix of the homogeneous electron gas at zero temperature using unbiased reptation Monte Carlo calculations for various densities and extrapolate the momentum distribution and the kinetic and potential energies to the thermodynamic limit. Our results on the renormalization factor allow us to validate approximate G0W0 calculations concerning quasiparticle p...

Benchmark Full Configuration Interaction Calculations for the Ground State of Three- Electron Harmonium Atoms

Two-dimensional electron gas near full polarization

We establish the consistency of the Fermi liquid description and find a relation between the Fermi liquid constants for a two-dimensional electron system near the point of full polarization due to a parallel magnetic field H. Our results enable us to predict connections between different thermodynamic properties of the system. In particular, we find that near the point of full polarization Hc ,...

Coupled cluster channels in the homogeneous electron gas.

We discuss diagrammatic modifications to the coupled cluster doubles (CCD) equations, wherein different groups of terms out of rings, ladders, crossed-rings, and mosaics can be removed to form approximations to the coupled cluster method, of interest due to their similarity with various types of random phase approximations. The finite uniform electron gas (UEG) is benchmarked for 14- and 54-ele...