Single‐crystalline CdS nanobelts demonstrate excellent field‐emission properties for the first time. Individual CdS nanobelts are assembled for high‐performance visible‐light photodetectors with an ultrafast response time of ∼20 μs and ultrahigh quantum efficiency of 1.9 × 107%. The results suggest a high potential of utilizing these CdS nanobelts as optoelectronic nanodevices.

The DNA binding profile of a series of dinuclear platinum complexes [{trans-PtCl-(L)2}2H2N(CH2)nNH2]2+ (L = NH3 or py; 1,1/t,t/NH3 and 1,1/t,t/py, respectively) and [{cis-PtCl-(NH3)2H2N(CH2)nNH2]2+ (1,1/c,c/NH3) was examined to compare the effects of geometrical isomerism and the presence of ligands other than NH3 in the coordination sphere. Steric effects, because of the geometry of the leaving groups cis to the diamine bridge or the presence of planar pyridine ligands, result in diminished binding to calf thymus DNA for these isomers. In contrast, the pyridine derivative shows a distinct binding preference for poly(dG-dC).poly(dG-dC) in comparison to both NH3 isomers. Both NH3 complexes induced the B-->Z transition in poly(dG-dC).poly(dG-dC), but the presence of a pyridine ligand stabilized the B conformation. The bifunctional binding of the NH3 isomers results in unwinding of supercoiled pUC19 plasmid DNA equivalent to cis-DDP, while the unwinding of the pyridine derivative is approximately twice that of the mononuclear trans-[PtCl2(py)2]. DNA-DNA interstrand cross-linking is very efficient for all three agents, but sequencing studies indicated that only the 1,1/t,t/NH3 derivative is capable of forming a (Pt,Pt) intrastrand cross-link to the adjacent guanines of a d(GpG) sequence. The effects on DNA caused by bifunctional binding of dinuclear complexes are compared with those from the mononuclear [PtCl2(NH3)2] isomers. The results are discussed with respect to the antitumor activity of the dinuclear series.

Blue rinse: A hybrid surfactant that comprises a hexavanadate cluster and two C18 alkyl chains shows unexpected blue luminescence (see picture). The luminescence arises from the interaction between the counterions and the hexavanadate clusters, and varies with the type of counterions. This behavior was confirmed by studying the self‐assembly of the hybrids with various counterions in different solvents.

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