Proton distribution in high-pressure delta-Al(OH)₃ and delta-AlOOH and isostructural In(OH)₃ and InOOH phases: Information from High-resolution ¹H CRAMPS NMR and Raman spectroscopy

Abstract

In order to shed light on the proton distributions and order/disorder in high-pressure delta-Al(OH)3 and delta-AlOOH and isostructural In(OH)3 and InOOH phases, high-resolution 1H CRAMPS (FSLG)-MAS NMR and Raman spectroscopy have been applied. The 1H CRAMPS-MAS NMR revealed two peaks each for delta-Al(OH)3 and In(OH)3, and one each for delta-AlOOH and InOOH. These results are consistent with crystal structures refined from X-ray and/or neutron diffraction. The Raman spectra are also in general agreement with the NMR results.