A comparative study of the electronic band structures of hydrogen-terminated silicon chains by density functional theory with and without GW correction

A comparative study of the electronic band structures of hydrogen-terminated silicon atomic chains with 〈 110 〉 and 〈 112 〉 orientations was conducted using density functional theory (DFT) both with and without GW correction. A direct band gap was revealed in the 〈 110 〉 chain and an indirect band gap was revealed in the 〈 112 〉 chain. The same order of the energy levels at specific k points was observed with both levels of theory. The GW correction to the energy difference of the conduction band minima at points Γ and X was within 0.16 eV and does not change the order of energy levels. This study supports the validity of DFT for the qualitative determination of electronic band structures of low-dimensional hydrogen-terminated silicon systems.