The band structures and effective masses of III-V semiconductors ͑InP, InAs, InSb, GaAs, and GaSb͒ are calculated using the GW method, the Heyd, Scuseria, and Ernzerhof hybrid functional, and modified Becke-Johnson combined with the local-density approximation ͑MBJLDA͒-a local potential optimized for the description of the fundamental band gaps ͓F. Tran and P. Blaha, Phys. Rev. Lett. 102, 226401 ͑2009͔͒. We find that MBJLDA yields an excellent description of the band gaps at high-symmetry points, on par with the hybrid functional and GW. However, the effective masses are generally overestimated by 20-30 % using the MB-JLDA local multiplicative potential. We believe this to be related to incorrect nearest-neighbor hopping elements, which are little affected by the choice of the local potential. Despite these shortcomings, the MBJLDA method might be a suitable approach for predicting or interpolating the full band dispersion, if only limited experimental data are available. Furthermore, the method is applicable to systems containing several thousand atoms where accurate quasiparticle methods are not applicable.

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[1] Aerosol samples were collected in the urban atmosphere of Beijing, China, by deploying a tethered balloon. Coarse particles (d > 1 mm) were individually analyzed using electron microscopes, to investigate the extent of dust modification by acidic gases in the atmosphere. Based on the elemental composition, irregularly shaped mineral dust was separated into carbonate and silicate groups. Both sulfate and nitrate were found to accumulate on carbonate more readily than silicate particles. Interestingly, spherical particles resembling Ca-carbonate in composition were spotted frequently in the samples. These Ca-rich spherical particles were more abundant under humid conditions, suggesting that they are deliquesced carbonate particles that formed in the atmosphere following the uptake of acidic gases. Sulfate and nitrate were more frequently detected in the Ca-rich spherical particles than in carbonate in the original solid form, indicating that the gas uptake efficiency of carbonate is further enhanced after the phase transition.

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