TY - JOUR
T1 - Quasiparticle self-consistent GW calculations of the electronic band structure of bulk and monolayer V2O5
AU - Bhandari, Churna
AU - Lambrecht, Walter R L
AU - Van Schilfgaarde, Mark
N1 - This article is not freely accessible but may be accessed through your institution.
PY - 2015/3/10
Y1 - 2015/3/10
N2 - Quasiparticle self-consistent (QS) GW calculations are performed for bulk and monolayer V2O5 The orbital character of the bands and the bulk monolayer difference at the LDA level are discussed first. We find that the QS GW self-energy overestimates the gap by an unusually large amount. The main reason for this is identified to be the lattice polarization effect: The large LO-TO splittings in this polar material enhance the screening and reduce the screened Coulomb interaction affecting the gap. The effect is estimated to reduce the screened Coulomb interaction and hence the self-energy by a factor 0.38 (for bulk) and brings the calculated optical response functions in fairly good agreement with experiment. For monolayer V2O5 we find that the QS GW gap varies as 1/L with L the size of the spacing between the monolayers in a supercell. This results from the long-range nature of the self-energy Σ=iGW and the similar 1/L behavior of the dielectric screening.
AB - Quasiparticle self-consistent (QS) GW calculations are performed for bulk and monolayer V2O5 The orbital character of the bands and the bulk monolayer difference at the LDA level are discussed first. We find that the QS GW self-energy overestimates the gap by an unusually large amount. The main reason for this is identified to be the lattice polarization effect: The large LO-TO splittings in this polar material enhance the screening and reduce the screened Coulomb interaction affecting the gap. The effect is estimated to reduce the screened Coulomb interaction and hence the self-energy by a factor 0.38 (for bulk) and brings the calculated optical response functions in fairly good agreement with experiment. For monolayer V2O5 we find that the QS GW gap varies as 1/L with L the size of the spacing between the monolayers in a supercell. This results from the long-range nature of the self-energy Σ=iGW and the similar 1/L behavior of the dielectric screening.
UR - http://www.scopus.com/inward/record.url?scp=84924362854&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.91.125116
DO - 10.1103/PhysRevB.91.125116
M3 - Article
AN - SCOPUS:84924362854
SN - 1098-0121
VL - 91
JO - Physical Review B (Condensed Matter and Materials Physics)
JF - Physical Review B (Condensed Matter and Materials Physics)
IS - 12-15
M1 - 125116
ER -