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Telluride misfit layer compounds are reported for the first time. These compounds were synthesized using a novel approach of structurally designing a precursor that would form the desired product upon low‐temperature annealing, which allows the synthesis of kinetically stable products that do not appear on the equilibrium phase diagram. Four new compounds of the [(PbTe)1.17]m(TiTe2)n family are reported, and their structures were examined by a variety of X‐ray diffraction techniques. [ABSTRACT FROM AUTHOR]

Telluride misfit layer compounds are reported for the first time. These compounds were synthesized using a novel approach of structurally designing a precursor that would form the desired product upon low‐temperature annealing, which allows the synthesis of kinetically stable products that do not appear on the equilibrium phase diagram. Four new compounds of the [(PbTe)1.17]m(TiTe2)n family are reported, and their structures were examined by a variety of X‐ray diffraction techniques. [ABSTRACT FROM AUTHOR]

By dimensionally constraining crystalline layers in a non‐epitaxial intergrowth, nanocrystal ensembles with well‐defined and precisely controlled size are prepared. Synchrotron X‐ray diffraction, electron microscopy, and density functional theory show that a size‐induced second‐order structural transition allows the crystal structure of a layered semiconductor (SnSe) to be continuously tuned by controlling the thickness of the individual layers. [ABSTRACT FROM AUTHOR]

The structures of three new misfit layer compounds, [(PbSe)0.99]1[WSe2]1, [(PbSe)1.00]1[MoSe2]1, and [(SnSe)1.03]1[MoSe2]1, prepared as thin films from designed elementally modulated reactant precursors, have been investigated by synchrotron X-ray diffraction and scanning transmission electron microscopy. This is the second report of a misfit layer compound based on tin selenide and the first structure determinations of tungsten- and molybdenum-containing misfit layer compounds. The compounds have mismatches in both the a- and b-axis (in-plane) lattice parameters of the component structural units, which result in misfit parameters, δ, both greater and smaller than zero. Pole figures of hk0-type reflections indicate that c-axis-oriented (basal plane) dichalcogenide-structured units are randomly oriented within the a- b plane. The widths of diffraction peaks of type hk0, 00 l, and hkl ( h, k ≠ 0; l ≠ 0) indicate coherence lengths of approximately (6 to 7) nm within the a- b plane, the full thickness of the film along the c-axis, and (1 to 2) nm in mixed-index directions, respectively, consistent with random rotational disorder between the constituents, commonly termed turbostratic disorder in the clay literature. The intensities of 00 l- and hk0-type diffraction peaks were modeled to determine the structure of atomic planes along the c axis and the projection of the constituent structures onto the a- b plane, respectively. [ABSTRACT FROM AUTHOR]

The structures of three new misfit layer compounds, [(PbSe)0.99]1[WSe2]1, [(PbSe)1.00]1[MoSe2]1, and [(SnSe)1.03]1[MoSe2]1, prepared as thin films from designed elementally modulated reactant precursors, have been investigated by synchrotron X-ray diffraction and scanning transmission electron microscopy. This is the second report of a misfit layer compound based on tin selenide and the first structure determinations of tungsten- and molybdenum-containing misfit layer compounds. The compounds have mismatches in both the a- and b-axis (in-plane) lattice parameters of the component structural units, which result in misfit parameters, δ, both greater and smaller than zero. Pole figures of hk0-type reflections indicate that c-axis-oriented (basal plane) dichalcogenide-structured units are randomly oriented within the a- b plane. The widths of diffraction peaks of type hk0, 00 l, and hkl ( h, k ≠ 0; l ≠ 0) indicate coherence lengths of approximately (6 to 7) nm within the a- b plane, the full thickness of the film along the c-axis, and (1 to 2) nm in mixed-index directions, respectively, consistent with random rotational disorder between the constituents, commonly termed turbostratic disorder in the clay literature. The intensities of 00 l- and hk0-type diffraction peaks were modeled to determine the structure of atomic planes along the c axis and the projection of the constituent structures onto the a- b plane, respectively. [ABSTRACT FROM AUTHOR]