GW quasiparticle bandgaps of anatase TiO2 starting from DFT+U

Abstract

We investigate the quasiparticle band structure of anatase TiO2, a wide gap semiconductor widely employed in photovoltaics and photocatalysis. We obtain GW quasiparticle energies starting from density-functional theory (DFT) calculations including Hubbard U corrections. Using a simple iterative procedure we determine the value of the Hubbard parameter yielding a vanishing quasiparticle correction to the fundamental band gap of anatase TiO2. The band gap (3.3 eV) calculated using this optimal Hubbard parameter is smaller than the value obtained by applying many-body perturbation theory to standard DFT eigenstates and eigenvalues (3.7 eV). We extend our analysis to the rutile polymorph of TiO2 and reach similar conclusions. Our work highlights the role of the starting non-interacting Hamiltonian in the calculation of GW quasiparticle energies in TiO2, and suggests an optimal Hubbard parameter for future calculations.

arXiv comment8 pages, 3 figures, 1 table

References in corpus (10)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• A linear response approach to the calculation of the effective interaction parameters in the LDA+U method
• Ab initio pseudopotentials for electronic structure calculations of poly-atomic systems using density-functional theory
• Quasiparticle Self-Consistent GW Theory
• Combining GW calculations with exact-exchange density-functional theory: An analysis of valence-band photoemission for compound semiconductors
• Self-Energy and Excitonic Effects in the Electronic and Optical Properties of TiO2 Crystalline Phases
• Quasiparticle and Optical Properties of Rutile and Anatase TiO${}_2$
• {\it Ab--initio} finite temperature excitons
• Effect of the quantistic zero-point atomic motion on the opto-electronic properties of diamond and trans-polyacetylene
• Hydrogen-bonded supramolecular assembly of dyes at nanostructured solar cell interfaces

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