A neutron diffraction study of a one-layer triclinic chlorite (penninite)

Abstract

The crystal structure of a one-layer triclinic chlorite (penninite) was refned from three-dimensional neutron diffraction data. The structure shows the IID-4 stacking type with the cell constants: a: 5.3266(7), b :9.232(l), c: 14.399(3)A, a : 90, P :97.16(l), y : 90. The refinement, including site occupancies of tetrahedral and octahedral positions, gave a final R(4 : 0.024 for space group CT. No cation ordering was detected in the talc sheets; cation ordering is, however, signiflcant in the brucite sheets. The hydrogen-bonding system with respect to the stability of the different polytypes is discussed.