Optical absorption, mass spectroscopy, magnetic susceptibility, electron spin resonance, and gas adsorption studies of the activated dehydration of silver-exchanged zeolite A show that principally diamagnetic silver clusters are formed by the activated extraction of oxygen from (oxidation of) the zeolite lattice. This oxidation is formally two-electron and, coupled with intrazeolitic silver ion mobility, can account for the concerted reduction of pairs of silver ions without the formation of stable paramagnetic clusters. The predominant charged cluster (B) formed in the sodalite unit has a low-energy absorption band centered at 2.72 eV and a higher lying excitation at 3.8-3.9 eV. The nuclearity of this cluster is uncertain, although it is >6 and <14. Another cluster (C) appears to coexist with cluster B and has excitations at 3.5-3.6, 4.1-4.2, and 4.9-5 eV. Sorption of olefins induces the competitive and reversible desorption of silver ions from cluster B and leads to the formation of C. Three distinct intermediates (absorption maxima at 2.9, 3.1, and 3.3 eV) have been identified during silver ion desorption from cluster B. Another intermediate (cluster A; band maximum at 3-3.1 eV) has also been identified en route to the formation of cluster B. A superposition of this 3-3.1-eV intermediate absorption of cluster A with the 2.72-eV absorption of cluster B gives the so-called yellow form of silver zeolite A. This yellow color had previously been assigned to linear and doubly charged (paramagnetic) silver trimers trapped in the sodalite unit by Gellens et al.

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Examination of even-odd distinction in magnetic susceptibility of silver nanoclusters on silver bromide in light of the Kubo effect

The predominant Charged silver Clusters formed in Ag ‐ Azeolite during mild (low‐temp.