摘要：

Silver molecules showing several distinct absorption bands within the range 2000-5550 A have been prepared under various experimental conditions using the matrix isolation technique. The absorption bands of silver molecules containing up to six atoms are clearly identified, allowing the remaining bands to be assigned mainly to larger silver molecules. Besides these distinct spectral features a broad absorption band in the spectral region from 2000-4500 A is also observed. This band consists of two overlapping absorption bands, a nearly constant absorption in the short wavelength region due to interband transitions and a plasma band with a peak maximum at approximately 3500 A. The close parallelism of the plasmon band properties. i.e. peak position, halfwidth and lineshape with those of larger silver particles (Me n, n > 1 00), either formed by the "gas evaporation" technique and/or in photosensitive glasses, gives strong evidence that two processes are involved in the cluster formation using the matrix technique - one which is closely related to a statistical growth of molecular aggregates and the other which results in the growth of silver microcrystals.

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