Shape Modulation of Octanuclear Cu(I) or Ag(I) Dichalcogeno Template Clusters with Respect to the Nature of their Encapsulated Anions: A Combined Theoretical and Experimental Investigation

Abstract

M8L6 clusters (M = Cu(I), Ag(I); L = dichalcogeno ligand) are known for their ability to encapsulate various kinds of saturated atomic anions. Calculations on the models [M8(E2PH2)6](2+) (M = Cu(I), Ag(I); E = S, Se) and the ionic or neutral [M8(X)(E2PH2)6](q) (X = H, F, Cl, Br, O, S, Se, N, P, C) indicate that the cubic M8L6 cage adapts its shape for maximizing the host-guest bonding interaction. The interplay between size, covalent and ionic bonding favors either a cubic, tetracapped tetrahedral, or bicapped octahedral structure of the metal framework. Whereas the large third- and fourth-row main group anions maintain the cubic shape, a distortion toward a tetracapped tetrahedral arrangement of the metals occurs in the case of hydride, fluoride, and oxide. The distortion is strong in the case of hydride, weak in the case of fluoride, and intermediate in the case of oxide. Density functional theory (DFT) calculations predict a bicapped octahedral architecture in the case of nitride and carbide. These computational results are supported by X-ray structures, including those of new fluorine- and oxygen-containing compounds. It is suggested that other oxygen-containing as well as so far unknown nitride-containing clusters should be feasible. For the first time, the dynamical behavior of the encapsulated hydride has been investigated by metadynamics simulations. Our results clearly demonstrate that the interconversion mechanism between two identical tetracapped tetrahedral configurations occurs through a succession of M-H bonds breaking and forming which present very low activation energies and which involve a rather large number of intermediate structures. This mechanism is full in accordance with (109)Ag and (1)H state NMR measurements.

Thermochromic Luminescent Materials and Multi-Emission Bands in d10 Clusters

“…However, in the case of the “opened” cluster, there is one Cu-Cu Wiberg bond index which is one order of magnitude smaller than the others (0.009). This result allows us to confirm that for the opened cluster the d 10 -d 10 interaction is weak10112223242526.…”

“…Among the thermochromic luminescent materials, the ones built with transition-metal complexes are of particular interest89101112. The analysis of the ordered molecular assemblies allows understanding and rationalizing the mechanisms that are involved in these phenomena.…”

Argentophilic Interactions

“…[(RO) 2 PS 2 ] À anions are attached to all six faces of the cube with each sulfur atom bridging two silver atoms (42, only one face shown covered with the dithiophosphonate ligand). [174][175][176] In the series [Ag 11 (S/Se){(S/Se) 2 P(OR) 2 } 6 X 3 ] with X = halogen and R = alkyl the environment of the nonacoordinate chalcogenide anion is a tricapped trigonal prism, and the edges of this polyhedron are within the same range of Ag-Ag distances. The two silver atoms capping the trigonal faces are not close to the sulfur/selenium center (43).…”

Validation of a computational protocol to simulate near IR phosphorescence spectra for Ru(II) and Ir(III) metal complexes

“…Furthermore, Density Functional Theory (DFT) and its TimeDependent extension (TD-DFT) are increasingly used to get electronic and vibrational information from small-to large-size systems thanks to the strong improvements in hardware and software [17][18][19][20][21][22][23]. Among all its possibilities, the DFT approach can be used for the prediction or confirmation of compounds [21,24,25] and the explanation of the luminescent and spectroscopic properties of multi-scale systems [13, [26][27][28][29][30][31][32][33].…”