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A structurally precise hydride‐containing Pt‐doped Cu‐rich nanocluster [PtH2Cu14{S2P(OiPr)2}6(CCPh)6] (1) has been synthesized. It consists of a bicapped icosahedral Cu14 cage that encapsulates a linear PtH2 unit. Upon the addition of two equivalents of CF3COOH to 1, two hydrido clusters are isolated. These clusters are [PtHCu11{S2P(OiPr)2}6(CCPh)4] (2), which is a vertex‐missing Cu11 cuboctahedron encaging a PtH moiety, and [PtH2Cu11{S2P(OiPr)2}6(CCPh)3] (3), a distorted 3,3,4,4,4‐pentacapped trigonal prismatic Cu11 cage enclosing a PtH2 unit. The electronic structure of 2, analyzed by Density Functional Theory, is a 2e superatom. The electrocatalytic activities of 1–3 for hydrogen evolution reaction (HER) were compared. Notably, Cluster 2 exhibited an exceptionally excellent HER activity within metal nanoclusters, with an onset potential of −0.03 V (at 10 mA cm−2), a Tafel slope of 39 mV dec−1, and consistent HER activity throughout 3000 cycles in 0.5 M H2SO4. Our study suggests that the accessible central Pt site plays a crucial role in the remarkable HER activity and may provide valuable insights for establishing correlations between catalyst structure and HER activity. [ABSTRACT FROM AUTHOR]

Although atomically precise polyhydrido copper nanoclusters are of prime interest for a variety of applications, they have so far remained scarce. Herein, this work describes the synthesis of a dithiophosphate‐protected copper(I) hydride‐rich nanocluster (NC), [Cu30H18{S2P(OnPr)2}12] (1H), fully characterized by various spectroscopic methods and single‐crystal X‐ray diffraction. The X‐ray structure of 1H reveals an unprecedented central Cu12 hollow icosahedron. Six faces of this icosahedron are capped by Cu3 triangles, the whole Cu30 core being wrapped by twelve dithiophosphate ligands and the whole cluster has ideal S6 symmetry. The locations of the 18 hydrides in 1H were ascertained by a single‐crystal neutron diffraction study. They are composed of three types: capping μ3‐H, interstitial μ4‐H (seesaw) and μ5‐H ligands (square pyramidal), in good agreement with the DFT simulations. The numbers of hydrides and ligand resonances in the 1H NMR spectrum of 1H are in line with their coordination environment in the solid state, retaining the S6 symmetry in solution. Furthermore, two new Se‐protected polyhydrido copper nanoclusters, [Cu30H18{Se2P(OR)2}12] (2H: R=iPr 3H: R=iBu) were synthesized from their sulfur relative 1H via ligand displacement reaction and their X‐ray structures feature the exceptional case where both the NC shape and size are fully conserved during the course of ligand exchange. DFT and TD‐DFT calculations allow understanding the bonding and optical properties of clusters 1H–3H. In addition, the reaction of 1H with [Pd(PPh3)2Cl2] in the presence of terminal alkynes led to the formation of new bimetallic Cu−Pd alloy clusters [PdCu14H2{S2P(OnPr)2}6(C≡CR)6] (4: R=Ph; 5: R=C6H4F). [ABSTRACT FROM AUTHOR]

The electronic structure of the spherical Mackay icosahedral nanosized cluster Pd55(PiPr3)12(μ3‐CO)20 is analyzed by using DFT calculations. Results reveal that it can be considered as a regular superatom with a "magic" electron count of 20, characterized by a 1S2 1P6 1D10 2S2jellium configuration. Its open shell nature is associated with partial occupation of non‐jellium, 4d‐type, levels located on the interior of the Pd55 kernel. This shows that the superatom model can be used to rationalize the bonding and stability of spherical ligated group 10 clusters, despite their apparent 0‐electron count. [ABSTRACT FROM AUTHOR]

Abstract: A templated galvanic exchange performed on [Ag20{Se2P(OiPr)2}12] of C3 symmetry with three equiv AuI yields a mixture of [Au1+xAg20−x{Se2P(OiPr)2}12]+ (x=0–2) from which [Au@Ag20{Se2P(OiPr)2}12]+ and [Au@Au2Ag18{Se2P(OiPr)2}12]+ are successfully characterized to have T and C1 symmetry, respectively. Crystal structural analyses combined with DFT calculations on the model compounds explicitly demonstrate that the central Ag0 of Ag20 being oxidized by AuI migrates to the protecting atomic shell as a new capping AgI, and both second and third Au dopants prefer occupying non‐adjacent icosahedron vertices. The differences in symmetry, T and C1, are manifested in the spatial orientation of their protecting atomic shell composed of eight capping Ag atoms as well as re‐construction upon the replacement of Ag atoms on the vertices of AuAg12 icosahedral core with second and third Au dopants. As a result, a unique pathway for substitutional‐doped clusters with increased nuclearity is proposed. [ABSTRACT FROM AUTHOR]

The synthesis and structural determination of a silver nanocluster [Ag20{S2P(OiPr)2}12] (2), which contains an intrinsic chiral metallic core, is produced by reduction of one silver ion from the eight-electron superatom complex [Ag21{S2P(OiPr)2}12](PF6) (1) by borohydrides. Singlecrystal X-ray analysis displays an Ag20 core of pseudo C3 symmetry comprising a silver-centered Ag13 icosahedron capped by seven silver atoms. Its n-propyl derivative, [Ag20{S2P(OnPr)2}12] (3), can also be prepared by the treatment of silver(I) salts and dithiophosphates in a stoichiometric ratio in the presence of excess amount of [BH4]-. Crystal structure analyses reveal that the capping silveratom positions relative to their icosahedral core are distinctly different in 2 and 3 and generate isomeric, chiral Ag20 cores. Both Ag20 clusters display an emission maximum in the near IR region. DFT calculations are consistent with a description within the superatom model of an 8- electron [Ag13]5+ core protected by a [Ag7{S2P(OR)2}12]5- external shell. Two additional structural variations are predicted by DFT, showing the potential for isomerism in such [Ag20{S2P(OR)2}12] species. [ABSTRACT FROM AUTHOR]

An air- and moisture-stable nanoscale polyhydrido copper cluster [Cu32(H)20{S2P(O iPr)2}12] ( 1H) was synthesized and structurally characterized. The molecular structure of 1H exhibits a hexacapped pseudo-rhombohedral core of 14 Cu atoms sandwiched between two nestlike triangular cupola fragments of (2×9) Cu atoms in an elongated triangular gyrobicupola polyhedron. The discrete Cu32 cluster is stabilized by 12 dithiophosphate ligands and a record number of 20 hydride ligands, which were found by high-resolution neutron diffraction to exhibit tri-, tetra-, and pentacoordinated hydrides in capping and interstitial modes. This result was further supported by a density functional theory investigation on the simplified model [Cu32(H)20(S2PH2)12]. [ABSTRACT FROM AUTHOR]