Crystal and electronic structures, transport properties of a ternary tungsten silicophosphide W3Si2P

Here we report a tungsten silicophosphide W3Si2P isostructural and isoelectronic to Mo3Si2P, which was prepared by heating the constituent elements at 1170 °C. It adopts a nonsymmorphic lattice with a-glide symmetry (noncentrosymmetric space group Ama2). The electrical and thermal transport properties were characterized by electrical resistivity, Seebeck effect and thermal conductivity (κ). W3Si2P shows metallic conduction following the Bloch-Grüneisen-Mott model with holes as the main carriers, which is also supported by ab-initio calculations. Electronic and lattice κ make comparable contributions to the thermal conduction at high temperatures, while the electronic component dominates at low temperatures. Electronic-structure calculations reveal that the W 5d orbits govern the bands near the Fermi level, in which 5dx2−y2 orbital electrons take the maximal occupation. As the first genuine ternary compound in W–Si–P family, it might be a novelty playground to probe the underlying electronic physics related to crystallographic symmetry. A tabulation summarizes the compounds in W–Si–P system, and reviews on their structural and physical properties were made to build a comprehensive understanding of this system. The synthesized W3Si2P adopts an orthorhombic structure consisting of (W1)Si2P3 trigonal bipyramids and (W2)Si5P2 convex octahedra, which exhibits metallicity with holes as the major carriers. Electronic and lattice κ make comparable contributions to the thermal conduction. [Display omitted] •A tungsten silicophosphide W3Si2P adopting the space group Ama2 was prepared.•W3Si2P exhibits metallic conduction with holes as the main charge carriers.•W 5d orbital electrons govern the bands and density of states near the Fermi level.•The thermal transport was analyzed by thermal conductivity measurement.•A review on the compounds in W–Si–P system has been made.