Hydrogen bond symmetrization and elastic constants under pressure of<i>δ</i>-AlOOH

Cortona, Pietro

doi:10.1088/1361-648x/aa791f

Cited by 14 publications

(11 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(i) the symmetrization P has a great variation, e.g. ≃120 GPa in ice-VII 7 – 9 compared to ≃15 GPa in δ -AlOOH 10 – 12 , (ii) proton tunnelling dominates the transition in ice-VII 7 , 8 , 13 – 15 , but is absent in δ -AlOOH 10 . (iii) The bulk modulus in ice-VII 8 , 16 , 17 shows a noticeable softening, while only a minor effect is found in δ -AlOOH 11 .…”

Section: Introductionmentioning

confidence: 99%

Structural independence of hydrogen-bond symmetrisation dynamics at extreme pressure conditions

et al. 2022

View full text Add to dashboard Cite

The experimental study of hydrogen-bonds and their symmetrization under extreme conditions is predominantly driven by diffraction methods, despite challenges of localising or probing the hydrogen subsystems directly. Until recently, H-bond symmetrization has been addressed in terms of either nuclear quantum effects, spin crossovers or direct structural transitions; often leading to contradictory interpretations when combined. Here, we present high-resolution in-situ 1H-NMR experiments in diamond anvil cells investigating a range of systems containing linear O-H ⋯ O units at pressure ranges of up to 90 GPa covering their respective H-bond symmetrization. We found pronounced minima in the pressure dependence of the NMR resonance line-widths associated with a maximum in hydrogen mobility, precursor to a localisation of hydrogen atoms. These minima, independent of the chemical environment of the O-H ⋯ O unit, can be found in a narrow range of oxygen oxygen distances between 2.44 and 2.45 Å, leading to an average critical oxygen-oxygen distance of $${\bar{r}}_{{{{{{{{\rm{OO}}}}}}}}}^{{{{{{{{\rm{crit}}}}}}}}}=2.443(1)$$ r ¯ OO crit = 2.443 ( 1 ) Å.

show abstract

Section: Introductionmentioning

confidence: 99%

Structural independence of hydrogen-bond symmetrisation dynamics at extreme pressure conditions

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Ab initio Density Functional Theory (DFT) calculations have reported discrepant results on the c ij behavior of δ‐AlOOH at high pressures (Cortona, 2017; Pillai et al., 2018; Tsuchiya & Tsuchiya, 2009). Our results are plotted together with Cortona (2017) and Tsuchiya and Tsuchiya (2009) in Figure S8 in Supporting Information . There is a very good agreement between our measured c 22 , c 44 , c 55 , c 66 , and c 13 values and those reported in the literature, whereas the other experimental c ij exhibit a different evolution with pressure (Figure S8 in Supporting Information ).…”

Section: Resultsmentioning

confidence: 99%

High‐Pressure Elasticity of δ‐(Al,Fe)OOH Single Crystals and Seismic Detectability of Hydrous MORB in the Shallow Lower Mantle

Satta

Criniti

Kurnosov

et al. 2021

Geophysical Research Letters

View full text Add to dashboard Cite

Oxyhydroxides like δ‐(Al,Fe)OOH may stabilize “water” in Mid‐Ocean Ridge Basalt (MORB) subducted into the Earth's lower mantle. The single‐crystal elasticity of δ‐(Al,Fe)OOH has not been experimentally constrained, hampering an accurate evaluation of the seismic detectability of this high‐pressure solid solution, and the presence of “water,” in the deep Earth. Here, we report the first experimental single‐crystal elasticity results of δ‐(Al0.97Fe0.03)OOH measured by X‐ray diffraction and Brillouin spectroscopy. We use our results to compute seismic properties of hydrous and anhydrous MORB at pressures and temperatures expected in slabs at shallow lower mantle conditions. We show that hydrous MORB is less dense than anhydrous MORB, but has faster aggregate seismic velocities. This suggests that hydration in MORB has an effect on velocities opposite to that observed in other lithologies, and further indicates that hydration of MORB increases the seismic contrast to the background mantle.

show abstract

“…Three exemplary scenarios will be used in order to illustrate the usefulness of this multidimensional NMR technique in high pressure research. Pure δ -AlOOH undergoes a subtle sub to supergroup phase transition from the P2 1 nm to the Pnnm phase at ∼ 10 GPa 38,39 and shows a hydrogen bond symmetrization at about 15 GPa [39][40][41] . This oxyhydroxide gained attention in the geophysics community due to its potential role as a carrier of hydrogen into the deeper regions of Earth's mantle [42][43][44][45] .…”

Section: B Two Dimensionsmentioning

confidence: 99%

In-situ High Pressure Nuclear Magnetic Resonance Crystallography

Meier¹,

Aslandukovа²,

Trybel³

et al. 2021

Preprint

View full text Add to dashboard Cite

Our recent developments in in-situ nuclear magnetic resonance (NMR) spectroscopy under extreme conditions led to the observations of a wide variety of physical phenomena not accessible with standard high pressure experimental probes. However, inherent di-or quadrupolar line broadening in diamond anvil cell (DAC) based NMR experiments often limit detailed investigations of local atomic structures, especially if different phases or local environments are coexisting. Here, we present our progress in the development of high resolution NMR experiments in DACs using oneand two-dimensional homonuclear decoupling experiments at pressures up to the Mbar regime. Using this technique, spectral resolutions in the order of 1 ppm and below have been achieved, enabling high pressure structural analysis. Several examples will demonstrate the wide applicability of this method for extreme conditions research.

show abstract

Hydrogen bond symmetrization and elastic constants under pressure ofδ-AlOOH

Cited by 14 publications

References 40 publications

Structural independence of hydrogen-bond symmetrisation dynamics at extreme pressure conditions

Structural independence of hydrogen-bond symmetrisation dynamics at extreme pressure conditions

High‐Pressure Elasticity of δ‐(Al,Fe)OOH Single Crystals and Seismic Detectability of Hydrous MORB in the Shallow Lower Mantle

In-situ High Pressure Nuclear Magnetic Resonance Crystallography

Contact Info

Product

Resources

About