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We have performed ab-initio self-consistent calculations using the full potential linear augmented plane wave method to investigate the structural and the electronic properties of the boron bismuth III -V compound BBi. Our calculations provide the first available information about the structural and electronic ground-state properties of BBi. Total energy calculations of the cubic zinc-blende, wurtzite, rock-salt, cesium chloride and orthorhombic Cmcm phases are made. The zinc-blende structure is found to be the ground-state phase of BBi; within the generalized gradient approximation (local density approximation), we found a lattice constant of 5.529 Å (5.416 Å) and a bulk modulus of 72.20 GPa (86.27 GPa). We found that, contrary to other boron compounds, the band gap of BBi is direct at the Γ point. The relativistic contraction of the 6s orbital of Bi has a strong influence on the bands and bonds of BBi. Consequently, the electronic properties of BBi are shown to differ considerably from those of common group III -V semiconductors (e.g. GaAs); in particular, we found an unusually strong p -p mixing of the valence-band maximum relative to most of the other III -V compounds. Furthermore, the calculated valence charge density shows an anomalous behavior, characterized by a charge transfer towards the 'cation' B atom, further illustrating the rich behavior of boron bismuth compounds.

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The recently discovered hexagonal wurtzite phase of several III–V nanowires opens up strong opportunity to engineer optoelectronic and transport properties of III–V materials. Herein, we explore the dynamical and dielectric properties of cubic (3C) and wurtzite (2H) III–V compounds (AlP, AlAs, AlSb, GaP, GaAs, GaSb, InP, InAs, and InSb). For cubic III–V compounds, our calculated phonon frequencies agree well with neutron diffraction and Raman-scattering measurements. In the case of 2H III–V materials, our calculated phonon modes at the zone-center Γ point are in distinguished agreement with available Raman-spectroscopy measurements of wurtzite GaAs, InP, GaP, and InAs nanowires. Particularly, the “fingerprint” of the wurtzite phase, which is our predicted E2(high) phonon mode, at 261 cm−1(GaAs), 308 cm−1(InP), 358 cm−1(GaP), and 214 cm−1(InAs) matches perfectly the respective Raman values of 258 cm−1, 306.4 cm−1, 353 cm−1, and 213.7 cm−1 for GaAs, InP, GaP, and InAs. Moreover, the dynamic charges and high-frequency dielectric constants are predicted for III–V materials in both cubic (3C) and hexagonal (2H) crystal polytypes. It is found that the dielectric properties of InAs and InSb contrast markedly from those of other 2H III–V compounds. Furthermore, InAs and InSb evidence relative strong anisotropy in their dielectric constants and Born effective charges, whereas GaP evinces the higher Born effective charge anisotropy of 2H III–V compounds.