We present a low-scaling diagrammatic Monte Carlo approach to molecular correlation energies. Using combinatorial graph theory encode many-body Hugenholtz diagrams, we sample the M\o{}ller-Plesset ($\mathrm{MP}n$) perturbation series, obtaining accurate energies up $n=5$, with quadratic scaling in number of basis functions. Our technique reduces computational complexity many-fermion problem, op...

Copper (Cu) remains the most important metal catalyst for carbon dioxide reduction reaction (CO2RR) into C2 products. Due to limited evidence from in situ experiments, mechanistic studies are often performed framework of density functional theory (DFT), using functionals at generalized gradient approximation (GGA) level, which have fundamental difficulties correctly describe CO adsorption and s...

Using a many-body theory, we calculate the change in differential conductance ∆dI/dV after adding an impurity either on a clean surface or inside an elliptic quantum corral. Using the same set of parameteres for both cases, the qualitative features of the voltage dependence of ∆dI/dV observed in recent experiments, are reproduced. Introduction In recent experiments a Co atom (acting as a magnet...

The three-step model (TSM) of high-harmonic generation (HHG) is generalized to atomic and molecular many-electron systems. Using many-body perturbation theory, corrections to the standard TSM due to exchange and electron-electron correlations are derived. It is shown that canonical Hartree-Fock orbitals represent the most appropriate set of one-electron states for calculating the HHG spectrum. ...

In the experiment of the quantum mirage, confinement of surface states in an elliptical corral has been used to project the Kondo effect from one focus where a magnetic impurity was placed, to the other empty focus. The signature of the Kondo effect is seen as a Fano antiresonance in scanning tunneling spectroscopy. This experiment combines the many-body physics of the Kondo effect with the sub...

A many-body theory of molecular junction transport based on nonequilibrium Green’s functions is developed, which treats coherent quantum effects and Coulomb interactions on an equal footing. The central quantity of the many-body theory is the Coulomb self-energy matrix ΣC of the junction. ΣC is evaluated exactly in the sequential tunneling limit, and the correction due to finite tunneling width...