The interface-modulated structure of TaSi_0.360Te₂

Abstract

The incommensurate modulation in the structure of TaSi 0.360 Te 2 has been determined by single-crystal X-ray diffraction. The (3+1)-dimensional superspace group is Pnma(00γ)s00, γ=0.3602 (8), basic unit-cell dimensions a=6.329 (3), b=14.031 (3), c=3.8258 (7) A, V=339.72 A 3 , Z=4. Refinement on 1907 reflections with I≥2.5σ(1) converged to R=0.097, R=0.064 for 521 main reflections, R=0.089 for 831 first-order satellites and R=0.174 for 555 second-order satellites. The structure can be regarded as based upon the structure of the commensurate parent compound TaSi 1/3 Te 2 modulated by the incommensurate insertion of interfaces consisting of units of the hypothetical orthorhombic commensurate compound TaSi 1/2 Te 2