Phase transformations in feldspar group minerals with paracelsian topology under high temperature and high pressure

LA Gorelova - Russian Geology and Geophysics, 2023 - pubs.geoscienceworld.org
Feldspar group minerals (feldspars) form up to 60 vol.% of the Earth's crust. The knowledge
of their stability under extreme conditions (high-pressure and high-temperature) allow to …

High-pressure crystal chemistry

CT Prewitt, RT Downs - Reviews in mineralogy, 1998 - degruyter.com
The response of earth materials to increasing pressures and temperatures is an area of
research that is of interest to many investigators in geochemistry and geophysics. There …

Structural stability of silica at high pressures and temperatures

AR Oganov, MJ Gillan, GD Price - Physical Review B—Condensed Matter and …, 2005 - APS
The high-pressure phase diagram of Si O 2 has been calculated using density-functional
perturbation theory. We find that phase transitions of silica do not correspond to any …

Formation and structure of a dense octahedral glass

M Guthrie, CA Tulk, CJ Benmore, J Xu, JL Yarger… - Physical Review Letters, 2004 - APS
We have performed in situ x-ray and neutron-diffraction measurements, and molecular
dynamics simulations, of G e O 2, an archetypal network-forming glass under pressure …

Mechanical strength and coordination defects in compressed silica glass: Molecular dynamics simulations

Y Liang, CR Miranda, S Scandolo - Physical Review B—Condensed Matter …, 2007 - APS
Contrary to ordinary solids, which are normally known to harden by compression, the
compressibility of Si O 2 (silica) glass has a maximum at about 2–4 GPa and its mechanical …

Anatomy of black veins in Zagami: clues to the formation of high-pressure phases

F Langenhorst, JP Poirier - Earth and Planetary Science Letters, 2000 - Elsevier
Black melt veins in the Martian basaltic meteorite Zagami were investigated using analytical
transmission electron microscopy, with the goal to constrain the mechanisms and PTt …

Local Defect Structures and Ion Transport Mechanisms in the Oxygen-Excess Apatite La9.67(SiO4)6O2.5

A Jones, PR Slater, MS Islam - Chemistry of Materials, 2008 - ACS Publications
Apatite-type oxides of general formula La9. 33+ x (SiO4) 6O2+ 3 x/2 have been attracting
considerable interest recently because of their observed high oxide-ion conductivity and …

The stability and P–V–T equation of state of CaSiO3 perovskite in the Earth's lower mantle

SH Shim, TS Duffy, G Shen - Journal of Geophysical Research …, 2000 - Wiley Online Library
Energy dispersive X‐ray diffraction measurements for polycrystalline CaSiO3 perovskite
were carried out at in situ transition zone and lower mantle P‐T conditions (P= 18–96 GPa …

Mixed alkali systems: structure and 29Si MASNMR of Li2Si2O5 and K2Si2O5

B De Jong, HTJ Supèr, AL Spek… - … Section B: Structural …, 1998 - journals.iucr.org
Li2Si2O5, Mr= 150.05, λ (Mo Kα)= 0.71073 Å, 293 K, orthorhombic, Ccc2, a= 5.807 (2), b=
14.582 (7), c= 4.773 (3) Å, V= 404.2 (3) Å3, μ (Mo Kα)= 0.78 mm− 1, Z= 4, Dx= 2.466 Mg m …

Charge distribution as a tool to investigate structural details. II. Extension to hydrogen bonds, distorted and hetero-ligand polyhedra

M Nespolo, G Ferraris, G Ivaldi… - … Section B: Structural …, 2001 - journals.iucr.org
It is shown that one of the main reasons for most failures of the methods for calculating
distance-dependent bond strengths is related to the distortion of the coordination polyhedra …