Nanocrystal arrays

In preliminary experiments we have shown that silver films thermally evaporated onto AAO substrates spontaneously form ordered nanocrystal arrays. In the present study we have prepared a series of Ag-coated AAO substrates with different silver mass thickness, and we have determined the optimum thickness of Ag film for SERS by observing the spectra of water-soluble cationic Cu(II)-tetrakis(4-N-methylpyridyl) porphyrin (CuTMpyP4). 

A key issue in nanostructured materials is the dipole coupling between nanocrystals which will cause the optical properties of a nanocrystal ensemble to become like those of the bulk material. There has been extensive investigation of the interactions between particles embedded within media for a range of boundary conditions. We have found that the effective dielectric function given by Eq. (10), based on the Maxwell-Garnett model [1] is very accurate for quite dense nanocrystal arrays. In practice, one measures the transmittance of a thin film of the dense nanoparticle based film. Conventional solutions are simply... 

Whetten, R. L., Shafigullin>l. N., etal. Crystal Structures of Molecular Gold Nanocrystal Arrays. Accounts of Chemical Research,32(5), 397-406 (1999). 

The low temperature 7-V characteristics behavior of doped R-hel PA nanofibers is similar to that observed in 2D metal nanocrystal arrays [87-90] as well as in ID chains of graphitized carbon... 

Zeolites constitute a group of hydrated crystalline aluminosilicates containing regularly shaped pores with sizes from 1 nm to several nanometers. This provides them with the ability to reversibly adsorb and desorb specific molecules. Chemical synthesis of semiconductors inside such pores permits the fabrication of regularly distributed, highly size-monodispersed nanocrystal arrays. This has been applied to CdS, Pbl2, and Ge. 

Harfenist SA, Wang ZL, Alvarez MM, Vezmar 1, Whetten RL (1996) Highly oriented molecular Ag nanocrystal arrays. J Phys Chem 100(3) 13904-13910... 

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