Electronic band gaps from quantum Monte Carlo methods
Yubo Yang, В. П. Горелов, Carlo Pierleoni, David M. Ceperley, Markus Holzmann
Abstract
Accurate prediction of the fundamental gap in insulators is a challenge for electronic structure theories. Electronic correlation and finite-size effects can significantly change the fundamental gap. Using quantum Monte Carlo, the authors show here that the fundamental gap can be calculated as the derivative discontinuity of the energy with respect to the electron density in the grand-canonical ensemble. Further, the finite-size error can be understood and corrected using information encoded in the electronic structure factor. The presented methodology applies for any explicitly correlated method.
Topics & Concepts
Quantum Monte CarloStatistical physicsMonte Carlo methodElectronic structureBand gapDiscontinuity (linguistics)QuantumPhysicsQuantum mechanicsMathematicsStatisticsMathematical analysisAdvanced Chemical Physics StudiesPhysics of Superconductivity and MagnetismMachine Learning in Materials Science