Crystal structure of a hydrogen sulfide sorption complex of anhydrous Mn2+-exchanged zeolite Y (FAU, Si/Al = 1.56)

Abstract

Abstract The structure of a hydrogen sulfide sorption complex of anhydrous Mn2+-exchanged zeolite Y, |Mn37.5(H2S)16.5|[Si117Al75O384]-Y, has been determined at 100(1) K by single-crystal synchrotron X-ray diffraction techniques in the cubic space group Fd 3 ¯ m. The complex was prepared by treating Mn37.5-Y with H2S(g), followed by evacuation for 0.5 h. The structure was refined using all intensities to the final error index R1 = 0.062 (for Fo > 4σ(Fo)). Mn2+ ions occupy four crystallographic sites. The 16 double 6-rings per unit cell are fully occupied, about 11 with a Mn2+ ion at their centers and 5 with a Mn2+ ion on each side. The remaining Mn2+ ions are found at two single-6-ring sites, about 11.5 in supercages and 5 in sodalite cavities. H2S molecules occupy two crystallographic sites, about 11.5 in supercages and 5 in sodalite cavities. Each supercage H2S molecule coordinates to a Mn2+ ion in a single 6-ring, and each sodalite H2S molecule bridges between two double-6-ring Mn2+ ions. The Mn-S bond lengths are 2.410(20) A and 2.49(23) A, respectively.