Magic-angle-spinning NMR shows the aluminosilicate framework of ultramarine to be disordered
Magic-angle-spinning NMR shows the aluminosilicate framework of ultramarine to be disordered
复制标题
魔角旋转核磁共振显示群青的铝硅酸盐骨架是无序的
作者：
J. Klinowski;S. Carr;S. Tarling;P. Barnes
29Si magic-angle-spinning NMR (MAS NMR) spectra of synthetic ultramarine show that the structure of its aluminosilicate framework is different from that of lazurite, its natural counterpart. Si-O-Si, Si-O-Al and Al-O-Al linkages are simultaneously present and Si and Al sites are disordered. This agrees with the results from the Rietveld refinement of neutron diffraction data and suggests that either the mechanisms of formation of lazurite and ultramarine are different or that the ordering process occurs on a long time scale.
