| Abstract
| - The three-dimensional structure of metastable exfoliated-restacked WS2 (r-WS2) has been determinedby the atomic pair distribution function (PDF) technique. We show that the structure of r-WS2is not a randomturbostratic assembly of layers, as previously thought, but it can be better regarded as a monoclinic structurewith considerable intrinsic disorder. At room temperature, the atomic-scale structure of r-WS2 is well describedin the space group P1121 of the monoclinic system with four formula units in the cell, and lattice parametersa = 3.270(5) Å, b = 5.717(5) Å, c = 12.309(5) Å, and γ = 88.43°. Analysis of the X-ray scattering data,collected with Synchrotron radiation (λ = 0.202 Å) over a wide scattering angle, shows that the metastablematerial is built of layers of distorted (WS6) octahedral units, in contrast to hexagonal 2H-WS2 which is builtof layers of perfect (WS6) trigonal prisms. A characteristic structural feature of the restacked material is thatW atoms within a single layer form zigzag chains along the a axis of the unit cell via short metal−metal bondsof length 2.77(1) and 2.85(1) Å, in agreement with previous two-dimensional electron diffraction studies.
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