Lattice dynamics and thermodynamic investigation of MNiSn (M = Hf, Ti and Zr) Half-Heusler compounds: Density functional theory approach

Quasi-harmonic approximation of lattice dynamics and thermodynamic properties of half Heusler ScXSb (x = Ni, Pd, Pt) from first principles

“…The compliance occurs between 75 J (K mol) −1 and 79 J (K mol) −1 for C p and C v in the three compounds, and is consistent with the report in reference [36] for ScNiSb alloy, where they reported C p approaches the Dulong-Petit compliance limit of 74.8 J (K mol) −1 . Though there are no reports in literature to compare the compliance to the Dulong-Petit limit of the compounds with, the limits obtained here, however compares favourably with other 18-valence electron reported in literature [51][52][53]. The behavior of the thermal expansion was analyzed, as seen in figure 6.…”

“…The expansion of monotonous rapid expansion of the compounds takes place at temperatures significantly below Θ D , and at temperatures above Θ D , the compounds exhibit strong harmonicity. ScNiSb remains competitive and relevant compared with some pristine half Heusler semiconductors reported in the literature [46][47][48][49].…”

Effect of Be and P doping on the electron density, electrical and optoelectronic conduct of half-Heusler LiMgN within ab initio scheme

“…The HH composites have the form XYZ, where X belongs to the first column of the main group, Y represents a rare earth element, transition metal or noble metal (X and Y=Zr, Cr, Na, K, Li, Zn, Cd, Mn, Ni, Ir, Co, and Fe), and Z denotes the sp-valent elements (Z=Al, Sn, Sb, P, In, Si, Ge, As, and Ga) [6][7][8]. HH has attracted extensive interest, not only because they use cheap, abundant, lightweight, and environment-friendly elements, but also because they combine high 'Seebeck -coefficients' with electrically moderately low resistivities, resulting in inherently high-power factors [9][10][11][12]. At high temperatures, many electrons become thermally excited from the 'valence band' to the 'conduction band', leaving behind them an equal number of holes.…”

“…Moreover, this alloy has a very strong covalent bond (Li-N and Mg-N) [56], in LiMgN, the bonding characteristic is due to the large electronegativity between (Mg and N) and the Li acts effectively as ( + Li ions ). Furthermore, the LiMgN is a commercially safe hydrogen storage alloy [57], abundant in nature resulting in lower material cost and environment-friendly elements [9][10][11][12]. Additionally, the LiMgN belonging to the ternary semiconducting compounds may also be easier to manufacture due to their crystal structures as compared to other materials of similar band gap [58].…”