Ab initio calculations of structural and electronic properties of WSe2 compound

Synergistic Effect of Phonon Localization and Band Convergence in a WSe2–WTe2 Superlattice Leads to High Thermoelectric Performance

“…The optimized crystal structure demonstrates an energetically lowest configuration with hexagonal unit cell a = b = 3.35 Å and c = 14.20 Å, accompanied by bond lengths of 2.55 Å (W–Se) and 2.70 Å (W–Te), as depicted in Figure c. The substitution of the lighter Se atom with the heavier Te atom in the superlattice leads to an increase in the lattice parameter and the bond length compared to the WSe 2 structure where a = b = 3.30 Å and c = 14.25 Å, closely aligning with the experimentally reported values ( a = 3.28 Å, c = 12.95 Å). − The superlattice structure shows a distinct shift in bond angles with values of 82.20° (W–Se–W) and 76.18° (W–Te–W), indicating disparities when compared to the bond angle 81.42° observed in WSe 2 for W–Se–W. These variations in bond angles can be attributed to the different atomic radii between Se and Te atoms.…”

Exploring Anisotropic Carrier Transport in WSe2–WTe2 Superlattices: A Computational Study

“…21 Moreover, extensive theoretical investigations employing first-principles calculations have been conducted to probe the characteristics of WSe 2 , a well-known p-type semiconductor featuring an indirect band gap of 1.20 eV which generally adopts the 2H crystal structure. 22 The "2H" notation refers to the hexagonal crystal structure. On the other hand, WTe 2 is a semimetal with orthorhombic (Td) crystal structure, displaying an extremely large magnetoresistance effect in its diamagnetic single crystal phase.…”

“…Moreover, extensive theoretical investigations employing first-principles calculations have been conducted to probe the characteristics of WSe 2 , a well-known p-type semiconductor featuring an indirect band gap of 1.20 eV which generally adopts the 2H crystal structure . The “2H” notation refers to the hexagonal crystal structure.…”