First-principles study of the elastic and thermodynamic properties of HfB2 with AlB2 structure under high pressure

Theoretical prediction of HfB2 monolayer, a two-dimensional Dirac cone material with remarkable Fermi velocity

“…The B-B bond length (1.85Å) is almost equivalent to that in the FeB 2 monolayer (1.83Å) 23 and slightly longer than those in the TiB 2 monolayer (1.79Å), 22 hydrogenated boron sheet (1.72Å) 24 and boron sheet (1.67Å). 38 The B-Hf bond length (2.32Å) is smaller than that in bulk HfB 2 (2.53Å), 39 indicating a much stronger interaction between the Hf atoms and boron layer.…”

Deformation and Hardness of UHTCs as a Function of Temperature

“…While theoretical predictions for the effect of increased pressure on elastic constants and phase stability of UHTCs are available (see, e.g., [4,14]), no predictions of the variation of the elastic constants with temperature were found. Experimentally, the most complete set of measurements are for ZrB 2 for which Okamoto and coworkers measured the variation of all five elastic constants with temperature up to 1400 K [12].…”

Electronic structure, phonon spectra and electron–phonon interaction in ScB2

“…Quite a number of theoretical studies of the electronic properties of the diborides are known to date [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. Ivanovskii et al [9] performed full potential linear muffin-tin orbital (FP-LMTO) calculations of all hexagonal diborides of 3d (Sc, Ti, ..., Fe), 4d (Y, Zr, ..., Ru), and 5d (La, Hf, ..., Os) metals and analyzed the variations in their chemical stability and some other properties (e.g., melting temperatures, enthalpies of formation).…”