Photoelectron properties of DNA and RNA bases from many-body perturbation theory

TL;DR

This study uses advanced many-body perturbation theory to accurately compute photoelectron properties of DNA and RNA bases, aligning well with experimental data and revealing insights into their electronic structure and lifetimes.

Contribution

It introduces an efficient G0W0-Lanczos method for converged quasiparticle calculations of DNA and RNA bases, highlighting the importance of optimal basis sets and detailed exchange-correlation analysis.

Findings

Calculated ionization potentials and electron affinities match experiments

Inverse lifetimes depend linearly on quasiparticle energies

Optimal polarizability basis improves GW calculation convergence

Abstract

The photoelectron properties of DNA and RNA bases are studied using many-body perturbation theory within the GW approximation, together with a recently developed Lanczos-chain approach. Calculated vertical ionization potentials, electron affinities, and total density of states are in good agreement with experimental values and photoemission spectra. The convergence benchmark demonstrates the importance of using an optimal polarizability basis in the GW calculations. A detailed analysis of the role of exchange and correlation in both many-body and density-functional theory calculations shows that while self-energy corrections are strongly orbital-dependent, they nevertheless remain almost constant for states that share the same bonding character. Finally, we report on the inverse lifetimes of DNA and RNA bases, that are found to depend linearly on quasi-particle energies for all deep valence states. In general, our G0W0-Lanczos approach provides an efficient yet accurate and fully converged description of quasiparticle properties of five DNA and RNA bases.