The crystal structure of a carbon disulfide sorption complex of dehydrated partially cobalt(II)-exchanged zeolite A

Abstract

The crystal structure of a carbon disulfide sorption complex of dehydrated partially Co(II)-exchanged zeolite A, Co 4Na 4A·4 CS 2 [ a = 12.145(2) A ̊ ], has been determined by single-crystal X-ray diffraction techniques in the cubic space group Pm3m at 21(1)°C. Co 4Na 4A was dehydrated at 360°C and 2 × 10 −6 Torr for 2 d, followed by exposure to ca. 290 Torr of carbon disulfide vapor at 21(2)°C for 1 h. The structure was refined to the final error indices R 1 = 0.060 and R 2 = 0.058 with 190 reflections for which l > 3 σ( l). In this structure, four Co 2+ ions and three Na + ions per unit cell lie at 6-oxygen ring positions: The Na + ions are recessed 0.61 Å into the sodalite unit and the Co(II) ions extend 0.48 Å into the large cavity. One Na + ion lies in an 8-oxygen ring plane. Four carbon disulfide molecules are sorbed per unit cell. Each bridges between a Co(II) ion and three 8-ring framework oxygens, and two of the four associate further with an 8-ring Na + ion. The two sulfur-to-carbon distances are normal: 1.56(11) and 1.56(12) Å.