Magnetism in Solid Oxygen Studied by High-Pressure Neutron Diffraction

Klotz, Stefan

doi:10.1007/s10909-018-1885-4

Cited by 4 publications

(3 citation statements)

References 46 publications

(111 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Nevertheless, pressure has been predicted to induce ferromagnetism in certain phases of alkali metals, 125,126 and pressure is experimentally known to induce magnetism in various iron alloys 127,128 Magnetic order for Fe under pressure is controversial, 129 as is that of O 2 . 130,131 As we will see when we discuss the atoms of the d-block, magnetism in atoms is not always predicted to increase upon compression. In several instances, the reverse is expected.…”

Section: T H I S C O N T E N T Imentioning

confidence: 98%

Squeezing All Elements in the Periodic Table: Electron Configuration and Electronegativity of the Atoms under Compression

et al. 2019

View full text Add to dashboard Cite

We present a quantum mechanical model capable of describing isotropic compression of single atoms in a non-reactive neon-like environment. Studies of 93 atoms predict drastic changes to ground-state electronic configurations and electronegativity in the pressure range of 0–300 GPa. This extension of atomic reference data assists in the working of chemical intuition at extreme pressure and can act as a guide to both experiments and computational efforts. For example, we can speculate on the existence of pressure-induced polarity (red-ox) inversions in various alloys. Our study confirms that the filling of energy levels in compressed atoms more closely follows the hydrogenic aufbau principle, where the ordering is determined by the principal quantum number. In contrast, the Madelung energy ordering rule is not predictive for atoms under compression. Magnetism may increase or decrease with pressure, depending on which atom is considered. However, Hund’s rule is never violated for single atoms in the considered pressure range. Important (and understandable) electron shifts, s→p, s→d, s→f, and d→f are essential chemical and physical consequences of compression. Among the specific intriguing changes predicted are an increase in the range between the most and least electronegative elements with compression; a rearrangement of electronegativities of the alkali metals with pressure, with Na becoming the most electropositive s1 element (while Li becomes a p group element and K and heavier become transition metals); phase transitions in Ca, Sr, and Ba correlating well with s→d transitions; spin-reduction in all d-block atoms for which the valence d-shell occupation is d n (4 ≤ n ≤ 8); d→f transitions in Ce, Dy, and Cm causing Ce to become the most electropositive element of the f-block; f→d transitions in Ho, Dy, and Tb and a s→f transition in Pu. At high pressure Sc and Ti become the most electropositive elements, while Ne, He, and F remain the most electronegative ones.

show abstract

Section: T H I S C O N T E N T Imentioning

confidence: 98%

Squeezing All Elements in the Periodic Table: Electron Configuration and Electronegativity of the Atoms under Compression

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The epsilon phase was considered to have no long-range magnetic ordering (23). Arguments on this issue are being revisited (24,25). XRS spectra would probably provide unique information on this if this kind of flux-limited experiment could be performed at low-temperature and high-pressure conditions.…”

Section: Resultsmentioning

confidence: 99%

“…The energy sampling k mesh was 5 × 5 × 7, which resulted in 88 k points. Calculations were performed at the non-spin-polarized condition as dense solid oxygen (the epsilon phase) is considered nonmagnetic or does not have any long-range magnetic order according to neutron studies (23,25). Details of the geometrical optimizations can be found elsewhere (16).…”

Section: Methodsmentioning

confidence: 99%

Electronic structure of dense solid oxygen from insulator to metal investigated with X-ray Raman scattering

Fukui

Wada²,

Hiraoka

et al. 2019

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Electronic structures of dense solid oxygen have been investigated up to 140 GPa with oxygen K-edge X-ray Raman scattering spectroscopy with the help of ab initio calculations based on density functional theory with semilocal metageneralized gradient approximation and nonlocal van der Waals density functionals. The present study demonstrates that the transition energies (Pi*, Sigma*, and the continuum) increase with compression, and the slopes of the pressure dependences then change at 94 GPa. The change in the slopes indicates that the electronic structure changes at the metallic transition. The change in the Pi* and Sigma* bands implies metallic characteristics of dense solid oxygen not only in the crystal a–b plane but also parallel to the c axis. The pressure evolution of the spectra also changes at ∼40 GPa. The experimental results are qualitatively reproduced in the calculations, indicating that dense solid oxygen transforms from insulator to metal via the semimetallic transition.

show abstract

First-principles description of solid oxygen in the gigapascal pressure scale using the DFT+vdW+U approach

Attaiaa,

Micoulaut,

Klotz

et al. 2024

Phys. Rev. B

View full text Add to dashboard Cite

Magnetism in Solid Oxygen Studied by High-Pressure Neutron Diffraction

Cited by 4 publications

References 46 publications

Squeezing All Elements in the Periodic Table: Electron Configuration and Electronegativity of the Atoms under Compression

Squeezing All Elements in the Periodic Table: Electron Configuration and Electronegativity of the Atoms under Compression

Electronic structure of dense solid oxygen from insulator to metal investigated with X-ray Raman scattering

First-principles description of solid oxygen in the gigapascal pressure scale using the DFT+vdW+U approach

Contact Info

Product

Resources

About