Correlation versus hybridization gap in CaMn\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$_{2}$$\end{document}2Bi\do

We study the interplay between electronic correlations and hybridization in the low‑energy electronic structure of CaMn 2 Bi 2 , a candidate hybridization‑gap semiconductor. By employing a DFT+ U approach we find both the antiferromagnetic Néel order and band gap in good agreement with the corresponding experimental values. Under hydrostatic pressure, we find a crossover from hybridization gap to charge‑transfer insulting physics due to the delicate balance of hybridization and correlations. Increasing the pressure above P c = 4 GPa we find a simultaneous pressure‑induced volume collapse, plane‑to‑chain, insulator to metal transition. Finally, we have also analyzed the topology in the antiferromagnetic CaMn 2 Bi 2 for all pressures studied. The electronic structure of fermionic correlated systems is driven by the competition between the tendencies of the electron to spread out as a wave and to localize as a particle, the latter usually accompanied with magnetism. That is, the interplay of the spin and charge degrees of freedom is a central issue 1 . Layered two-dimensional (2D) materials provide a unique platform for studying this dual nature of the electronic states which produces rich phase diagrams including high temperature superconductivity 2–4 , non-trivial topological insulating and semi-metallic phases 5 , quantum spin liquid states 6 , and strange metal behavior 7 . In