Opening band gaps of low-dimensional materials at the meta-GGA level of density functional approximations

Neupane, Bimal; Tang, Hong; Nepal, Niraj K.; Adhikari, Santosh; Ruzsinszky, Adrienn

doi:10.1103/physrevmaterials.5.063803

Cited by 22 publications

(24 citation statements)

References 87 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, we also found that r 2 SCAN sometimes overestimates the bandgaps of narrow-gap insulators. This is consistent with the tendency of the TASK meta-GGA 36 to overestimate the gaps of narrow-gap insulators 37 .…”

Section: Discussionsupporting

confidence: 87%

“…For example, SnSe has an experimental bandgap of 0.91 eV; SCAN predicts a 0.89 eV gap, whereas r 2 SCAN predicts a much larger 1.06 eV gap. A similar tendency to overestimate the gaps of small-gap insulators has been observed 37 for the TASK 36 meta-GGA, which was designed for accurate bandgap prediction. The r 2 SCAN bandgap tends to be more accurate across all insulators than SCAN's: r 2 SCAN (SCAN) makes a 1.15 (1.20) eV MAE for this set.…”

Section: Bandgapssupporting

confidence: 62%

See 1 more Smart Citation

Testing the r$^2$SCAN density functional for the thermodynamic stability of solids with and without a van der Waals correction

Kothakonda¹,

Kaplan²,

Isaacs³

et al. 2022

Preprint

View full text Add to dashboard Cite

A central aim of materials discovery is an accurate and numerically reliable description of thermodynamic properties, such as the enthalpies of formation and decomposition. The r 2 SCAN revision of the strongly constrained and appropriately normed (SCAN) meta-generalized gradient approximation (meta-GGA) balances numerical stability with high general accuracy. To assess the r 2 SCAN description of solid-state thermodynamics, we evaluate the formation and decomposition enthalpies, equilibrium volumes, and fundamental bandgaps of more than 1,000 solids using r 2 SCAN, SCAN, and PBE, as well as two dispersion-corrected variants, SCAN+rVV10 and r 2 SCAN+rVV10. We show that r 2 SCAN achieves accuracy comparable to SCAN and often improves upon SCAN's already excellent accuracy. Whereas SCAN+rVV10 is often observed to worsen the formation enthalpies of SCAN, and makes no substantial correction to SCAN's cell volume predictions, r 2 SCAN+rVV10 predicts marginally less-accurate formation enthalpies than r 2 SCAN, and slightly more-accurate cell volumes than r 2 SCAN. The average absolute errors in predicted formation enthalpies are found to decrease by a factor of 1.5 to 2.5 from the GGA level to the meta-GGA level. Smaller decreases in error are observed for decomposition enthalpies. For formation enthalpies r 2 SCAN improves over SCAN for intermetallic systems. For a few classes of systems -transition metals, intermetallics, weakly-bound solids, and enthalpies of decomposition into compounds -GGAs are comparable to meta-GGAs. In total, r 2 SCAN and r 2 SCAN+rVV10 can be recommended as stable, general-purpose meta-GGAs for materials discovery.

show abstract

Section: Discussionsupporting

confidence: 87%

Section: Bandgapssupporting

confidence: 62%

Testing the r$^2$SCAN density functional for the thermodynamic stability of solids with and without a van der Waals correction

Kothakonda¹,

Kaplan²,

Isaacs³

et al. 2022

Preprint

View full text Add to dashboard Cite

show abstract

“…The p-orbital EG of Z4CrI 3 is better described by mTASK, consistent with reports for other p-orbital materials. 28,30 The change of EG with bending is larger for wider nanoribbons Z6CrI 3 and Z8CrI 3 , as shown in Figure 2c.…”

Section: ■ Introductionmentioning

confidence: 79%

“…Our DFT calculations 24−28 show that for narrow CrI 3 nanoribbons, the ferromagnetic state with out-of-plane spin moments is almost equally stable with the one with in-plane spin moments, different from the monolayer CrI 3 . The recently developed mTASK metaGGA 28 gives improved magnetic moments and edge band gaps for CrI 3 nanoribbons, showing an improved description for p-orbitalderived edge states. We also use the full spinor enabled GW-BSE to study the optical absorption and magneto-optical properties of the CrI 3 magnetic nanoribbon.…”

Section: ■ Introductionmentioning

confidence: 99%

Density Functional Theory Study of Controllable Optical Absorptions and Magneto-Optical Properties of Magnetic CrI₃ Nanoribbons: Implications for Compact 2D Magnetic Devices

Tang

Neupane

Yan

et al. 2022

ACS Appl. Nano Mater.

View full text Add to dashboard Cite

A chromium triiodide (CrI3) monolayer has an interesting ferromagnetic ground state. In this work, we calculate band structures and magnetic moments of tensile-strained and bent zigzag CrI3 nanoribbons with density functional theory. The edge iodine atoms form flat low-lying conduction bands and couple with chromium atoms ferromagnetically, while the non-edge iodine atoms weakly couple antiferromagnetically. Narrow CrI3 nanoribbons have two locally stable magnetic moment orientations, namely, out-of-plane and in-plane (along the nanoribbon periodic direction) configurations. This enables four magnetization states in CrI3 nanoribbons, including two out-of-plane ones (up and down) and two in-plane ones (forward and backward along the nanoribbon periodical direction), increasing the operating controllability. Based on the one-dimensional Ising spin chain model, the spin correlation length of the narrow CrI3 nanoribbon is estimated to be about 10 Å at its estimated Curie temperature of 27 K, which is lower than the measured 45 K of the monolayer CrI3. The optical absorption and magneto-optical properties of CrI3 nanoribbons are investigated with many-body perturbation GW-BSE (Bethe–Salpeter equation), including magnetic dichroism and Faraday and magneto-optical Kerr effects. The low-energy dark excitons are mainly from transitions between electrons and holes with unlike spins and are non-Frenkel-like, while the bright excitons have mixed spin configurations. The intrinsic lifetime of excitons can be over one nanosecond, suitable for quantum information processes. Tensile strains and bending manifestly modulate the absorption spectra and magneto-optical properties of CrI3 nanoribbons within a technologically important photon energy range of ∼1.0–2.0 eV. The CrI3 nanoribbons can be used in 1D or 2D magnetic storage nanodevices, tunable magnetic optoelectronics, and spin-based quantum information controls.

show abstract

“…We, therefore, limited the calculated band gap of 2D materials covering the visible spectrum, ranging from 1.8 to 3.4 eV. 5 All band gaps were calculated using the mTASK functional, 30 which has been shown to predict the band gap of 2D materials accurately. 31 Interestingly, only two candidates (PrOBr and HoTe 2 ClO 5 ) satisfy this band gap criterion.…”

mentioning

confidence: 99%

Computation-Aided Discovery and Synthesis of 2D PrOBr Photocatalyst

Wang

Zhang

et al. 2022

ACS Energy Lett.

View full text Add to dashboard Cite

Developing photocatalysts is essential for converting solar energy into chemical fuels. Herein, we report the discovery and synthesis of praseodymium oxyhide (PrOBr), a two-dimensional (2D) rare-earth material, as an efficient photocatalyst. By performing high-throughput screening over popular computational 2D materials databases, we have identified 2D PrOBr as a promising photocatalyst with potentially good stability and activity. 2D PrOBr was successfully synthesized via the exfoliation of bulk PrOBr powders. The intrinsic photocatalytic activities of this 2D material were further validated. The measured hydrogen evolution rate of water splitting and the methane production rate of carbon dioxide reduction are 60.28 μmol•h −1 •g −1 and 0.862 μmol•h −1 •g −1 , which are about 3−6 times and 7 times higher than that of the typical 2D photocatalysts (e.g., 2D C 3 N 4 and BiOCl), respectively.

show abstract

Opening band gaps of low-dimensional materials at the meta-GGA level of density functional approximations

Cited by 22 publications

References 87 publications

Testing the r$^2$SCAN density functional for the thermodynamic stability of solids with and without a van der Waals correction

Testing the r$^2$SCAN density functional for the thermodynamic stability of solids with and without a van der Waals correction

Density Functional Theory Study of Controllable Optical Absorptions and Magneto-Optical Properties of Magnetic CrI₃ Nanoribbons: Implications for Compact 2D Magnetic Devices

Computation-Aided Discovery and Synthesis of 2D PrOBr Photocatalyst

Contact Info

Product

Resources

About

Opening band gaps of low-dimensional materials at the meta-GGA level of density functional approximations

Cited by 22 publications

References 87 publications

Testing the r$^2$SCAN density functional for the thermodynamic stability of solids with and without a van der Waals correction

Testing the r$^2$SCAN density functional for the thermodynamic stability of solids with and without a van der Waals correction

Density Functional Theory Study of Controllable Optical Absorptions and Magneto-Optical Properties of Magnetic CrI3 Nanoribbons: Implications for Compact 2D Magnetic Devices

Computation-Aided Discovery and Synthesis of 2D PrOBr Photocatalyst

Contact Info

Product

Resources

About

Density Functional Theory Study of Controllable Optical Absorptions and Magneto-Optical Properties of Magnetic CrI₃ Nanoribbons: Implications for Compact 2D Magnetic Devices