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The lattice symmetry chiefly determines the structure of the XeF ion in CsXeF7. The influence of the lone pair of electrons is here very weak, and the anion has a capped octahedral structure (C3v symmetry). The dinuclear anion Xe2F in NO2Xe2F13 can be structurally divided into an XeF6 molecule and an XeF ion. In this case the anion XeF is a capped trigonal prism (C2v symmetry).

A special composite of the cerium-based metal–organic framework (Ce-UiO-66) modified with graphitic carbon nitride nanosheets (g-C3N4) has been synthesized. In order to make a comparison, a series of composites comprising...

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with p-H,NC,H,SO,Na, gold/palladium colloids can be isolated as a silver grey, metallic looking precipitate. Such colloids are soluble in water giving a brown color.HRTEM investigations of these colloids show different intergranular structural images than the Au/Pt combinations. Two different types of particles can be distinguished. In Figure 2, right, one particle with the whole structure ordered is shown, as indicated by the optical diffractogram inserted. A comparison of this particle with the Au/Pd particle A in Figure 2, left, shows that the Au/Pd particle has a smoother surface-most likely resulting in a smaller surface area. The dark nucleus of the Au/Pd particle can be interpreted as the gold core, which is surrounded by the lighter shell of well-ordered palladium atoms. This will turn up more clearly for the lighter Pd shell compared to Pt.The second type of structure for the Au/Pd case is similar to the type B of Au/Pt in Figure 2 in such a way that the particle also gives an optical diffractogram of "polycrystalline" type ( Fig. 3, left). The intergranular structure has also in this case a smoother surface compared to the Au/Pt case. The HRTEM image of the approximately spherical specimen also shows a darker core. :

A capped octahedron, a capped trigonal prism, and a pentagonal bipyramid are the three structural types possible for compounds with coordination number 7. TeF 7−, CH3OTeF 6−, and trans‐(CH3O)2TeF 5− are all pentagonal bipyramidal; the large methoxy groups take up axial positions. The equatorial F atoms deviate slightly from an ideal plane. The picture on the right shows the crystal structure of TeF 7−, which contains fourfold disordered equatorial fluorine atoms.