Sulfide-mediated growth of NIR luminescent Pd/Ag atomically precise nanoclusters.

An essential feature of coinage metal nanoclusters (NCs) is their photoluminescence (PL), which spans a wide range of wavelengths from visible to near-infrared regions (NIR-I/II). A key challenge for synthetic chemists is to develop materials capable of efficient spectral change with maximum efficiency. Herein, we report novel dithiolate-protected bimetallic Pd-Ag NCs of the type [PdAgS{SP(OR)}] (R = Pr, 1Pr and Bu, 1Bu) and [PdAgS{SP(OBu)}] (2Bu).

Cuprophilic Interactions in Polymeric [CuO(Mes)].

The properties of cuprophilic compounds and the underlying fundamental principles responsible for the Cu(I)···Cu(I) interactions have been the subject of intense research as their diverse structural and physical attributes are being explored. In this light, we performed a new study of the compound [CuO(Mes)] reported by Haakansson et al. using state of the art experimental and theoretical analysis techniques.

Controlled aggregation of Pt/PtH/Rh/RhH doped silver superatomic nanoclusters into 16-electron supermolecules.

The assembly of discrete superatomic nanoclusters into larger constructs is a significant stride towards developing a new set of artificial/pseudo-elements. Herein, we describe a novel series of 16-electron supermolecules derived from the combination of discrete 8-electron superatomic synthons containing interstitial hydrides as vertex-sharing building blocks. The symmetric (RhH)Ag[SP(OPr)] (1) and asymmetric PtHPtAg[SP(OPr)] (2) are characterized by ESI-MS, SCXRD, NMR, UV-vis absorption spectra, electrochemical and computational methods.

C-H bond activation at antimony(III): synthesis and reactivity of Sb(III)-oxyaryl species.

We report on the synthesis, structure and reactivity of [{NCN}Sb(CH-Bu-3,5-O-4)] (3), an organoantimony(III)-oxyaryl species obtained upon C-H bond activation in a phenolate ligand and stabilised by the monoanionic pincer {NCN}. The mechanism leading to the formation of 3 is highly sensitive to steric considerations. It was probed experimentally and by DFT calculations, and a number of intermediates and related complexes were identified.

Protic Processes in an Extended Pyrazinacene: The Case of Dihydrotetradecaazaheptacene.

Pyrazinacenes are linearly fused heteroaromatic rings, with N atoms replacing all apical CH moieties. Component rings may exist in a reduced state, having NH groups instead of N, causing cross-conjugation. These compounds have interesting optical and electronic properties, including strong fluorescence in the near-infrared region and photocatalytic properties, leading to diverse possible applications in bio-imaging and organic synthesis, as well as obvious molecular electronic uses.

Barium phosphidoboranes and related calcium complexes.

The attempted synthesis of [{Carb}BaPPh] (1) showed this barium-phosphide and its thf adducts, 1·thf and 1·(thf), to be unstable in solution. Our strategy to circumvent the fragility of these compounds involved the use of phosphinoboranes HPPh·BH and HPPh·B(CF) instead of HPPh. This allowed for the synthesis of [{Carb}Ae{PPh·BH}] (Ae = Ba, 2; Ca, 3), [{Carb}Ca{(HB)PPh}·(thf)] (4), [{Carb}Ba{PPh·B(CF)}] (5), [{Carb}Ba{O(B(CF))CHCHCHCHPPh}·thf] (6), [Ba{O(B(CF))CHCHCHCHPPh}·(thf)] (7) and [Ba{PPh·B(CF)}·(thp)] (8) that were characterised by multinuclear NMR spectroscopy (thp = tetrahydropyran).

Doping effect on a two-electron silver nanocluster.

This study investigates the effects of metal addition and doping of a 2-electron silver superatom, [Ag{SP(OPr)}] (Ag10). When Ag is added to Ag10 in THF solution, [Ag{SP(OPr)}(OTf)] (Ag11) is rapidly formed almost quantitatively. When the same method is used with Cu, a mixture of alloys, [CuAg{SP(OPr)}] ( = 1-3, CuxAg11-x), is obtained.

Assignment of individual structures from intermetalloid nickel gallium cluster ensembles.

Poorly selective mixed-metal cluster synthesis and separation yield reaction solutions of inseparable intermetalloid cluster mixtures, which are often discarded. High-resolution mass spectrometry, however, can provide precise compositional data of such product mixtures. Structure assignments can be achieved by advanced computational screening and consideration of the complete structural space.

All-Hydrocarbon-Ligated Superatomic Gold/Aluminum Clusters.

Key strategies in cluster synthesis include the use of modulating agents (e.g., coordinating additives).

Diselenophosphate Ligands as a Surface Engineering Tool in PdH-Doped Silver Superatomic Nanoclusters.

The first hydride-doped Pd/Ag superatoms stabilized by selenolates are reported: [PdHAg(dsep)] [dsep = SeP(OPr)] and [PdHAg(dsep)] . was derived from the targeted transformation of [PdHAg(dtp)] [dtp = SP(OPr)] by ligand exchange, whereas was obtained from the addition of trifluoroacetic acid to , resulting in a symmetric redistribution of the capping silver atoms. The transformations are all achieved while retaining an 8-electron superatomic configuration.

Hydride-Containing Pt-doped Cu-rich Nanoclusters: Synthesis, Structure, and Electrocatalytic Hydrogen Evolution.

A structurally precise hydride-containing Pt-doped Cu-rich nanocluster [PtH Cu {S P(O Pr) } (CCPh) ] (1) has been synthesized. It consists of a bicapped icosahedral Cu cage that encapsulates a linear PtH unit. Upon the addition of two equivalents of CF COOH to 1, two hydrido clusters are isolated.

Hydride Doping Effects on the Structure and Properties of Eight-Electron Rh/Ag Superatoms: The [RhH@Ag{SP(OPr)}] ( = 0-2) Series.

Three hitherto unknown eight-electron rhodium/silver alloy nanoclusters, [RhAg{SP(OPr)}] (), [RhHAg{SP(OPr)}] (), and [RhHAg{SP(OPr)}] (), have been isolated and fully characterized. Cluster contains a regular Rh@Ag icosahedral core, whereas and exhibit distorted RhH@Ag and RhH@Ag icosahedral cores. The single-crystal neutron structure of located the encapsulated hydride at the center of an enlarged RhAg tetrahedron.

A heteroleptic fused bi-cuboctahedral Cu21S2 cluster.

A new dicationic cluster, [CuS{SCNBu}(CPh)], where the Cu21S2 kernel consists of two S@Cu cuboctahedra sharing a triangular Cu face is reported. Its waist part is bridged by three dithiocarbamate ligands, each in a hexaconnective, hexametallic (μ, μ) coordination pattern, an unprecedented feature in Cu nanocluster chemistry.

Metal-Metal Bonding in Late Transition-Metal [ML] Complexes: Exploring the Limits of the Isolobal Analogy between the CO and AlCp* Ligands.

Late dinuclear transition-metal (especially group 10 and 11) homoleptic carbonyl complexes are elusive species and have so far not been isolated. A typical example is the 30-electron species [Ni(CO)], the structure and bonding of which is still debated. We show that, by using the AlCp* ligand (isolobal to CO), it is possible to isolate and fully characterize [Ni(AlCp*)] (), which inspired us to revisit by DFT calculations, the bonding situation within [NiL] (L = CO, AlCp*) and other isoelectronic species.

Catalytic Alkyne Semihydrogenation with Polyhydride Ni/Ga Clusters.

The bimetallic, decanuclear Ni Ga -cluster of the formula [Ni (GaTMP) (μ -GaTMP) (μ -GaTMP)] (1, TMP=2,2,6,6-tetramethylpiperidinyl) reacts reversibly with dihydrogen under the formation of a series of (poly-)hydride clusters 2. Low-temperature 2D NMR experiments at -80 °C show that 2 consist of a mixture of a di- (2 ), tetra- (2 ) and hexahydride species (2 ). The structures of 2 and 2 are assessed by a combination of 2D NMR spectroscopy and DFT calculations.

Monocarboxylate-protected two-electron silver nanoclusters with high photothermal conversion performance.

The first series of monocarboxylate-protected silver nanoclusters was synthesized and fully characterized by X-ray diffraction, fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and electrospray ionization mass spectrometry (ESI-MS). Specifically, compounds [Ag(L)(9-AnCO)] (L = PhP (I), (4-ClPh)P (II), (2-furyl)P (III), and PhAs (IV)) were prepared by a solvent-thermal method under alkaline conditions. These clusters exhibit a similar unprecedented structure containing a [Ag@Ag] metal kernel, of which the 2-electron [Ag] inner core shows a flattened and puckered hexagonal bipyramid of symmetry.

Galvanic replacement-induced introduction of a heteroligand into bimetallic and trimetallic nanoclusters.

Heteroleptic 8-electron silver-rich alloy nanoclusters, [Au@AuAg(dtp)(PPh)] (1) and [Pt@AuAg(dtp)(PPh)] (2), were successfully synthesized a galvanic replacement reaction of 1,1-dithiolate-protected M@Ag (M = Au and Pt) nanoclusters with Au(I)-phosphine salts, leading to the alteration of the cluster nuclearity and geometry of shell skeletons but retaining the same 8-electron count.

Controlled Shell and Kernel Modifications of Atomically Precise Pd/Ag Superatomic Nanoclusters.

The first 8-electron Pd/Ag superatomic alloys with an interstitial hydride [PdHAg (dtp) ] (dtp=S P(O Pr) ) 1 and [PdHAg (dtp) ] 2 are reported. The targeted addition of a single Ag atom to 1 is achieved by the reaction of one equivalent of trifluoroacetic acid, resulting in the formation of 2 in 55 % yield. Further modification of the shell results in the formation of [PdAg (dtp) ] 3 via an internal redox reaction, with the system retaining an 8-electron superatomic configuration.

Superatom Pruning by Diphosphine Ligands as a Chemical Scissor.

A two-electron silver superatom, [Ag{SP(OPr)}(dppm)] (), was synthesized by adding dppm (bis(diphenylphosphino)methane) into [Ag{SP(OPr)}] (8e). It was characterized by single-crystal crystallography, multinuclear NMR spectroscopy, electrospray ionization-mass spectrometry, density functional theory (DFT), and time-dependent DFT calculations. The added dppm ligands, which carry out the nanocluster-to-nanocluster transformation, act as a chemical scissor to prune the nanocluster geometrically from an icosahedron-based Ag nanocluster (NC) to an octahedral Ag NC and electronically from eight-electron to two-electron.

Hydride-containing 2-Electron Pd/Cu Superatoms as Catalysts for Efficient Electrochemical Hydrogen Evolution.

The first hydride-containing 2-electron palladium/copper alloys, [PdHCu {S P(O Pr) } (C≡CPh) ] (PdHCu ) and [PdHCu {S P(O Pr) } {S PO(O Pr)} (C≡CPh) ] (PdHCu ), are synthesized from the reaction of [PdH Cu {S P(O Pr) } (C≡CPh) ] (PdH Cu ) with trifluoroacetic acid (TFA). X-ray diffraction reveals that the PdHCu and PdHCu kernels consist of a central PdH unit encapsulated within a vertex-missing Cu cuboctahedron and complete Cu cuboctahedron, respectively. DFT calculations indicate that both PdHCu and PdHCu can be considered as axially-distorted 2-electron superatoms.

From 8- to 18-Cluster Electrons Superatoms: Evaluation via DFT Calculations of the Ligand-Protected W@Au(dppm) Cluster Displaying Distinctive Electronic and Optical Properties.

The iconic W@Au icosahedral bare cluster reaches the favorable closed-shell superatomic electron configuration 1S 1P 1D, making it an 18-cluster electron (18-ce) superatom. Here, we pursue the evaluation of a ligand-protected counterpart based on the construction of a fully phosphine-protected [W@Au(dppm)] cluster strongly related to the characterized [Au(dppm)] homometallic counterpart. The later cluster has the same total number of valence electrons as the former but is considered an 8-ce superatom with 1S 1P configuration.

Phosphorescent cyclometalated platinum(II) complexes with phenyldiazine N^C ligands.

A series of phosphorescent platinum(II) complexes containing various phenyldiazine-type bidentate N^C ligands have been successfully synthesized and characterized. Structural modifications have been made to bidentate cyclometalating ligands regarding the nature of the diazine ring (pyrimidine, pyrazine and quinazoline), the substituent groups at the C4 position of the pyrimidine ring (OCH, CF) and the EDGs at the position of the Pt atom (OCH, Ph, NPh, carbazol). In addition, the electronic properties of the azaheterocyclic ancillary ligand have been modulated in this series of complexes (pyridine, 4-methoxy-pyridine or pyrimidine).

Unusual core engineering on a copper hydride nanoball.

A neutral polyhydrido copper cluster, [CuH{SCNBu}] (abbreviated as [CuH]), was prepared by the reaction of dithiocarbamates (dtc), Cu(I) salts and NaBH. The isolated cluster provides insights into core engineering, demonstrating its novel ability to reversibly add or remove one copper atom from the cluster core. Single-crystal X-ray analysis reveals that the new core-shell structure exhibits a Cu rhombicuboctahedral outer cage and an inner Cu triangular kernel.

Surface modifications of eight-electron palladium silver superatomic alloys.

Atomically precise thiolate-protected coinage metal nanoclusters and their alloys are far more numerous than their selenium congeners, the synthesis of which remains extremely challenging. Herein, we report the synthesis of a series of atomically defined dithiophosph(in)ate protected eight-electron superatomic palladium silver nanoalloys [PdAg{SPR}], 2a-c (where R = OPr, a; OBu, b; Ph, c) via ligand exchange and/or co-reduction methods. The ligand exchange reaction on [PdAg{SP(OPr)}], 1, with [NH{SePR}] (where R = OPr, or OPr) leads to the formation of [PdAg{SeP(OPr)}] (3) and [PdAg{SeP(OPr)}] (4), respectively.