Ordering of water in opals with different microstructures

Eckert, Jürgen
Gourdon, Olivier
Jacob, Dorrit E
Akgül, Çağla
Monteiro, Paulo JM
Vogel, Sven C
Wirth, Richard
Wenk, HansRudolf
Opal has long fascinated scientists. It is one of the few minerals with an amorphous structure, and yet, compared to silica glass, it is highly organized on the mesoscale. By means of inelastic neutron scattering (INS), we could document that in four samples of opal at low temperature an ice-like structure of water is present, with details depending on microstructural characteristics. While FTIR spectra for all samples are nearly identical and thus not very informative, INS shows clear differences, highlighting the significance of microstructures. Neutron diffraction at 100 K on one of the opal samples provides evidence for crystalline cubic ice.


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Citation Formats
J. Eckert et al., “Ordering of water in opals with different microstructures,” EUROPEAN JOURNAL OF MINERALOGY, pp. 203–213, 2015, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/46543.