Physical properties of high-nuclearity metal cluster compounds

Jongh, L.J. de; Brom, H.B.; Longoni, Giuliano; Nugteren, P. R.; Pronk, B.J.; Schmid, G.; Smit, H. H. A.; Staveren, M. P. J. van; Thiel, R.C.

doi:10.1007/978-3-642-74913-1_101

Cited by 5 publications

(4 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, they provide excellent model systems for monodispersed metal clusters, embedded in a dielectric matrix for the investigation of physical properties related to nanoscale particles. Among the various clusters, Au 55 (PPh 3 ) 12 Cl 6 (in short Au 55 ) and Pt 309 Phen 36 O 30 (in short Pt 309 ), have been intensely studied by different groups [2][3][4][5][6]. The possible electronic application of these metal clusters, with diameters of 1.4-2.1 nm, as "quantum dots" was first discussed by Schön and Simon [7].…”

mentioning

confidence: 98%

Single-electron tunneling in Au 55 cluster monolayers

Chi

Hartig

Drechsler

et al. 1998

Applied Physics A: Materials Science & Processing

Self Cite

View full text Add to dashboard Cite

Metallic nanometer clusters composed of 55 gold atoms isolated from each other by a thin organic ligand film, with a total diameter of 2.1 nm, were fabricated as monolayers on various technically relevant substrates by using a two-step self-assembly (SA) procedure as well as combined Langmuir-Blodgett (LB) and SA techniques. Scanning tunneling microscopy (STM) and scanning force microscopy (SFM) studies on these systems reveal a short-range close packing of these clusters. Single-electron tunneling (SET) phenomena, including Coulomb blockade and Coulomb staircase, are studied by local tunneling spectroscopy (LTS) at room temperature as well as at low temperature (90-100 K). A narrow spread of the charge energy is observed on such prepared cluster monolayers.In recent years, nanometer-sized clusters of metals separated from each other by organic ligand shells have received increasing scientific interest [1]. These clusters have a welldefined size in the metal core, with a fixed number of metal atoms, and are stabilized by the organic ligand shell. Thus, they provide excellent model systems for monodispersed metal clusters, embedded in a dielectric matrix for the investigation of physical properties related to nanoscale particles. Among the various clusters, Au 55 (PPh 3 ) 12 Cl 6 (in short Au 55 ) and Pt 309 Phen 36 O 30 (in short Pt 309 ), have been intensely studied by different groups [2-6]. The possible electronic application of these metal clusters, with diameters of 1.4-2.1 nm, as "quantum dots" was first discussed by Schön and Simon [7].Scanning tunneling microscopy and local tunneling spectroscopy has been applied to measure the electronic properties of compact Au 55 cluster pellets [8] or solvent-evaporated Au 55 and Pt 309 clusters on various substrates [9, 10]. Singleelectron tunneling on these systems has been clearly observed in the current-voltage (I-V ) curves. In previous investigations, the cluster solutions were dropped on a substrate and then dried, or the clusters were compressed to a pellet. The * Corresponding author quantitative analysis of I-V curves is based to some extend on the undefined geometric packing of the clusters. The charge energy had a wider spread than expected [10]. Further, in LTS investigations, one interesting question is addressed: whether the additional structures on the Coulomb staircase measured at 4.2 K might be induced by the interaction between the substrate and the clusters or by that between the ligand molecules and the metal core [10]. A uniform packing of clusters on the substrate will help to rule out some unknown effects for the quantitative analysis, since modification of the charging energy of a cluster might be affected by its environment. In addition, achieving ordered arrays of these metal dots is an essential step for developing nanoscale electronic devices [11].Recently, the closed packing of gold clusters, each encapsulated by a monolayer of alkyl thiol molecules, has been successfully achieved by spin casting [12]. As is known, spin casting of suspens...

show abstract

mentioning

confidence: 98%

Single-electron tunneling in Au 55 cluster monolayers

Chi

Hartig

Drechsler

et al. 1998

Applied Physics A: Materials Science & Processing

Self Cite

View full text Add to dashboard Cite

show abstract

“…Recent work on the Kondo effect in quantum wires, however, has demonstrated that new phenomena emerge when such systems are reduced to mesoscopic size [2]. In general, little is known about physics at these length scales apart from localization studies, and the cluster analogs of itinerant magnets [3,4]. We approach this problem from the other side, namely, by building up from the atomic length scale, towards more complicated mesoscopic systems.…”

mentioning

confidence: 99%

“…For this purpose, we have synthesized a new class of cluster compounds: Ni9Te6 rt+ and CogTee"" 1 " with n =0,1,2. These materials offer some unique properties: (1) The clusters are completely identical, order in a regular lattice, and large single crystals can be grown; (2) the passivating ligands form a weak bond to the cluster (different from, e.g., the metal-carbonyl clusters [4]); and (3) the clusters can be obtained in various charge states, without changing the structure significantly.…”

mentioning

confidence: 99%

Electron correlations on a mesoscopic scale: Magnetic properties of transition metal telluride cluster compounds

et al. 1993

View full text Add to dashboard Cite

We report the magnetic properties of a new class of materials: Ni9Te6 w+ and Co6Te8 w+ with n =0,1,2. These cluster compounds, which can be charged by chemical means from neutral to 2 + , provide a unique and novel way to change the Fermi level. For most charge states we observe quenching of the spin and orbital moments at low temperatures, accompanied by a large value for the temperature independent susceptibility of the ground state. The generic presence of low-energy magnetic excitations in these compounds indicates that these systems exhibit strong electron correlations and form mesoscopic analogs of the mixed-valence-heavy-fermion compounds.

show abstract

“…Wet chemical reduction procedures have been applied in the last 20 years or so to combine practically all transi- tion metals with different types of stabilizers, and the whole range of chemical reducing agents has successfully been applied. Bimetallic nanoclusters that were made accessible by this method have been thoroughly characterized [65][66][67][68][69][70][71][72][73][74][75][76][77][78][79][80]. Clusters of Au 55 were uniformly formed when a stream of B 2 H 6 was carefully introduced into a Au III ion solution.…”

Section: Reducing Agentsmentioning

confidence: 99%