Тип публикации: статья из журнала
Год издания: 2020
Идентификатор DOI: 10.1080/08957959.2020.1830078
Ключевые слова: 3.65 angstrom-phase, dense hydrous magnesium silicates, raman spectra, high pressure, six-coordinated silicon, 3.65 å-phase
Аннотация: 3.65 angstrom-phase (or hydroxide-perovskite), MgSi(OH)(6), is a representative of dense hydrous magnesium silicates (DHMS) with maximum water content (up to similar to 35 wt.% H2O) and thus is of interest as one of the largest repositories of water among all the known hydrous phases. Sample of 3.65 angstrom-phase, grown in DIA-typПоказать полностьюe multianvil apparatus, was studied by Raman spectroscopy under pressure up to similar to 7 GPa with diamond anvil cell. Interpretation of the Raman spectrum was carried out using lattice-dynamical simulations within ab initio DFT method (CASTEP code). Additionally, OH-stretching bands are analyzed with two phenomenological models: empirical model by Novak and Libowitzky, using correlation between O-O distance and the wavenumber of the OH-stretching band, and theoretical model, using double Morse potentials of hydrogen bond O-H center dot center dot center dot O. Upon the pressure increase, octahedral and bending delta(OH) vibrations exhibit linear positive pressure shift, whereas wavenumbers of the OH-stretching modes show inverse pressure dependence.
Журнал: HIGH PRESSURE RESEARCH
Выпуск журнала: Vol. 40, Is. 4
Номера страниц: 495-510
ISSN журнала: 08957959
Место издания: ABINGDON
Издатель: TAYLOR & FRANCIS LTD