Using InCl Vapor to Ion Exchange Indium into Zeolite Na–Y. Single-Crystal Structure of |In25.8Cl0.8Na37.0|[Si121Al71O384]–FAU Containing In+, In3+, and In57+–Cl––In57+
journal contributionposted on 22.02.2016, 13:01 by Dipak Sen, Nam Ho Heo, Ho-Cheol Kang, Karl Seff
Indium ions have been introduced into zeolite Y (FAU, Si/Al = 1.69) by an anhydrous vapor phase ion exchange (VPIE) method. In+16.7In3+1.1(In57+–Cl––In57+)0.8Na+37.0–Y was prepared by the reaction of fully dehydrated Na71–Y with a very low pressure of InCl(g) at T ≤ 623 K. Its structure at 294 K was determined using single-crystal crystallography with synchrotron X-radiation and was refined in the space group Fd3m̅ (a = 24.927(1) Å) to the final error index R1 = 0.038. In57+ cationic clusters center 1.6 of the 8 sodalite cavities per unit cell. In57+ is a centered tetrahedron with In–In = 2.763(7) Å; each terminal atom bonds to three framework oxygen atoms of a double 6-ring with In–O = 2.329(4) Å and O–In–O = 104.9(2)°. One terminal atom of each In57+ cluster also bonds to a chloride ion at site I, which in turn bonds linearly to a terminal atom of another In57+ cluster. In this way, the 1.6 In57+ units are linked together in pairs by 0.8 chloride ions to give 0.8 In57+–Cl––In57+ clusters per unit cell. The remaining indium cations occupy five nonframework crystallographic sites: 1.1 In3+ at site I′, 4.1 In+ at a second I′ site, 1.0 In+ at site II, 7.6 In+ at site III′, and 4.0 In+ at a second III′ site. Most of the Na+ ions, 31.0, complete the filling of site II; the remaining 6.0 are at site III.