Giuseppettite, chemical formula Na42K16Ca6Si48Al48O192(SO4)10Cl2 Æ 5H2O, space group P31c, a ¼ 12:856, c ¼ 42:256 A, is the 16-layer member of the cancrinite–sodalite group. It is characterised by an ABABABACBABABABC. . . stacking sequence of layers. The crystal structure of giuseppettite was solved and refined against data collected at the Elettra synchrotron facility, using a 0.3 · 0.2 · 0.2 mm3 single crystal, twinned on (0 0 1), k ¼ 0:9989 A, R ¼ 0:074 for 3769 reflections, R ¼ 0:073 for 3706 reflections with Fo > 4rðFoÞ. The structure contains two big cages (‘‘giuseppettite’’ cages) along ½0; 0; z, and sequences CCSCCCS of ‘‘cancrinite’’ (C) and ‘‘sodalite’’ cages (S) both along ½1=3; 2=3; z and ½2=3; 1=3; z. Four sulphate groups surrounded by sodium cations, and alternated with potassium cations, are located within the giuseppettite cages, whereas a partially ordered distribution of sulphate groups and chlorine anions occurs within the sodalite cages. The cancrinite cages host sodium cations and water molecules.
The crystal structure of giuseppettite, the 16-layer member of the cancrinite-sodalite group
BONACCORSI, ELENA
2004-01-01
Abstract
Giuseppettite, chemical formula Na42K16Ca6Si48Al48O192(SO4)10Cl2 Æ 5H2O, space group P31c, a ¼ 12:856, c ¼ 42:256 A, is the 16-layer member of the cancrinite–sodalite group. It is characterised by an ABABABACBABABABC. . . stacking sequence of layers. The crystal structure of giuseppettite was solved and refined against data collected at the Elettra synchrotron facility, using a 0.3 · 0.2 · 0.2 mm3 single crystal, twinned on (0 0 1), k ¼ 0:9989 A, R ¼ 0:074 for 3769 reflections, R ¼ 0:073 for 3706 reflections with Fo > 4rðFoÞ. The structure contains two big cages (‘‘giuseppettite’’ cages) along ½0; 0; z, and sequences CCSCCCS of ‘‘cancrinite’’ (C) and ‘‘sodalite’’ cages (S) both along ½1=3; 2=3; z and ½2=3; 1=3; z. Four sulphate groups surrounded by sodium cations, and alternated with potassium cations, are located within the giuseppettite cages, whereas a partially ordered distribution of sulphate groups and chlorine anions occurs within the sodalite cages. The cancrinite cages host sodium cations and water molecules.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
