Fully indium-exchanged zeolite Y, lIn~+_(62.6)(In5~(7+))_(1.2)lSi_(121)Al_(71)O_(384), was prepared by thallous ion exchange (TIE), a vapor phase ion exchange method. InCl(g, 510 Pa) was allowed to react with a single crystal of TI_(71)—Y under anhydrous conditions at 623 K. A second crystal prepared as above was washed with deionized water and redehydrated to give Hn~+_(39.7) (In5~(7+))_(4.5)lSi_(121)Al_(71)O_(384). The structures of fully dehydrated Tl_(71)—Y and these two forms of In—Y were determined by single-crystal crystallography using synchrotron X-radiation. Then the two In—Y crystals were subjected to scanning electron microscopy energy-dispersive X-ray (SEM-EDX) analysis. Both methods indicated that no Tl remained in the In—Y crystals. The additional steps of washing and redehydration caused some of the In~+ ions in the first In—Y crystal to disproportionate to give additional In5(7+) clusters in the sodalite cavities and In~0 atoms on the crystal surface. Most of the In~+ ions in both forms of In—Y are easily accessible to guest molecules via the 12-ring channel system.
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