Magnetic and structural properties of Fe-doped layered cobaltite TbBaCo1.91Fe0.09O5.5 at high pressures

Interest in hydrogen as a future energy carrier in mobile applications has led to a strong increase in research on the structural properties of complex alkali metal and alkaline earth hydrides, with the aim to find structural phases with higher hydrogen densities. This contribution reviews recent work on the structural properties and phase diagrams of these complex hydrides under elevated pressures, an area where rapid progress has been made over the last few years. The materials discussed in greatest detail are LiAlH4, NaAlH4, Li3AlH6, Na3AlH6, LiBH4, NaBH4, and KBH4. All of these have been studied under high pressure by various methods such as X-ray or neutron scattering, Raman spectroscopy, differential thermal analysis or thermal conductivity measurements in order to find information on their structural phase diagrams. Based mainly on experimental studies, preliminary or partial phase diagrams are also given for six of these materials. In addition to this information, data are provided also on experimental results for a number of other complex hydrides, and theoretical predictions of new phases and structures under high pressures are reviewed for several materials not yet studied experimentally under high pressure.

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Effect of High Pressures on the Electrical and Structural Properties of Fullerene С70

Bulletin of the Russian Academy of Sciences Physics ◽

10.3103/s1062873819060273 ◽

2019 ◽

Vol 83 (6) ◽

pp. 730-732

Author(s):

D. N. Sokolovsky ◽

P. S. Zelenovskiy ◽

Ya. Yu. Volkova

Keyword(s):

Structural Properties ◽

High Pressures

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Synthesis, microstructure and effect of high pressures on transport properties of GdBaCo2O5,5

Transaction Kola Science Cetnre ◽

10.37614/2307-5252.2021.2.5.050 ◽

2021 ◽

Vol 12 (2-2021) ◽

pp. 247-252

Author(s):

T. N. Tarasenko ◽

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T. S. Sivachenko ◽

I. Yu. Reshidova ◽

V. V. Burkhovetskii ◽

...

Keyword(s):

Phase Transition ◽

Transition Temperature ◽

Hysteresis Loop ◽

High Pressures ◽

Strong Dependence ◽

Thermal Relaxation ◽

Temperature Hysteresis ◽

First Order ◽

M Phase ◽

Layered Cobaltite

In polycrystalline samples of double layered cobaltite GdBaCo2O5.5 the structure and resistivity at the first order “insulator-metal” (I-M) phase transition were studied at normal and high pressures. The strong dependence of the shape of the temperature hysteresis loop on the rate of temperature change indicates an infra-slow thermal relaxation of conductivity. Baric studies have shown an increase in the transition temperature ТIM at increasing pressure P with baric coefficient dТIM/dP ≈ 10 K/GPa. The spin blockade model is used to explain the observed effects.

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Electronic and structural properties of fluid selenium at high pressures and temperatures – a new mechanism of non-metal-to-metal transition

Journal of Non-Crystalline Solids ◽

10.1016/s0022-3093(99)00131-3 ◽

1999 ◽

Vol 250-252 ◽

pp. 510-518 ◽

Cited By ~ 10

Author(s):

Fumiko Yonezawa ◽

Hiroaki Ohtani ◽

Toshio Yamaguchi

Keyword(s):

Structural Properties ◽

High Pressures ◽

High Pressures And Temperatures ◽

Electronic And Structural Properties

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