Elastic, electronic and optical properties of new 2D and 3D boron nitrides.

The current work investigates a novel three-dimensional boron nitride called bulk BN and its corresponding two-dimensional monolayer BN based on the first-principles of density functional theory. The phonon spectra prove that bulk BN and monolayer BN are dynamically stable. The molecular dynamics simulations verify that bulk BN and monolayer BN have excellent thermal stability of withstanding temperature up to 1000 K.

Electronic structures and physical properties of double perovskite ACoNbO (A = Sr, Ba) crystals.

The crystal structures, mechanical properties, lattice dynamics, electronic structures and optical properties of SrCoNbO and BaCoNbO have been studied by the first principles of density functional theory. The theoretically obtained crystal parameters of SrCoNbO and BaCoNbO are consistent with their experimental ones. Both SrCoNbO and BaCoNbO belong to the [Formula: see text] space group at the low-temperature limit and have very weak elastic anisotropy.

Electronic, Optical, and Lattice Dynamical Properties of Tetracalcium Trialuminate (Ca₄Al₆O).

The electronic, optical, and lattice dynamical properties of tetracalcium trialuminate (Ca₄Al₆O) with a special sodalite cage structure were calculated based on the density functional theory. Theoretical results show that Ca₄Al₆O is ductile and weakly anisotropic. The calculated Young's modulus and Poisson ratio are 34.