On the hardness of a new boron phase, orthorhombic γ-B28

@article{Solozhenko2008OnTH,
  title={On the hardness of a new boron phase, orthorhombic $\gamma$-B28},
  author={Vladimir L. Solozhenko and Oleksandr O. Kurakevych and Artem R. Oganov},
  journal={Journal of Superhard Materials},
  year={2008},
  volume={30},
  pages={428-429}
}
Measurements of the hardness of a new high-pressure boron phase, orthorhombic γ-B28, are reported. According to the data obtained, γ-B28 has the highest hardness (∼ 50 GPa) of all known crystal-line modifications of boron. 
Comparative review of theoretical and experimental equations of state of orthorhombic boron γ-B28
AbsractVarious theoretical and experimental 300 K equations of state of γ-B28, a new ultrahard high pressure orthorhombic phase of boron, have been reviewed. Throughout analyses and critical
High-Pressure Synthesis of Novel Superhard Phases in the B-C-N-O System
Recent results on high pressure–high temperature synthesis of new superhard phases in the B–C–N–O system (cubic B–C–N phases, diamond-like BC5, rhombohedral B13N2, orthorhombic γ-B28, etc.) are
High-pressure synthesis of novel superhard phases in the B‒C‒N system: recent achievements
Very recent results on high-pressure–high-temperature synthesis of novel superhard phases in the B‒C‒N system (diamond-like BC5, rhombohedral B13N2, nanocrystalline cubic boron nitride, orthorhombic
Superhard semiconducting optically transparent high pressure phase of boron.
TLDR
An orthorhombic (space group Pnnm) boron phase was synthesized at pressures above 9 GPa and high temperature, and it was demonstrated to be stable at least up to 30 GPa, and to be the second hardest elemental material after diamond.
High-pressure route to superhard boron-rich solids
Novel superhard phases are expected to be found among various high-pressure polymorphs of light element compounds. Besides diamond-like phases, the icosahedral boron-rich solids are of particular
Band Gap of Semiconducting High Pressure Phase of Boron
The partially ionic high pressure phase of boron γ-B28 was synthesized at 12 GPa 1500oC using a multi-anvil press. The crystal structure of γ-B28 was confirmed by x-ray diffraction. The γ-B28 phase
Crystal structure of dense pseudo-cubic boron allotrope, pc-B52, by powder X-ray diffraction
During past years, a number of reports have been published on synthesis of tetragonal allotrope of boron, t-B52 phase. However, no unambiguous characterization of the crystal structure has been
New high-pressure form of boron is significantly ionic
The comment of Dubrovinskaia et al. is scientifically flawed. The high-pressure form of boron, discovered by Oganov et al., is indeed new and its bonding has a significant ionic character, as
...
...

References

SHOWING 1-10 OF 22 REFERENCES
Structure refinement of the boron suboxide B6O by the Rietveld method
The structure of the boron suboxide B6O has been refined by the Rietveld method applied on X‐ray powder diffraction data. The samples were prepared by hot pressing amorphous boron and B2O3 and the
Thermodynamic aspects of materials’ hardness: prediction of novel superhard high-pressure phases
In the present work, we have proposed a method that allows one to easily estimate the hardness and bulk modulus of known or hypothetical solid phases from the data on Gibbs energy of atomization of
Boron-rich solids
This report contains papers on research with boron-rich solids. These papers main describe the following topics: electronic structure; electronic and optical properties; superconductivity; crystal
Ionic high-pressure form of elemental boron
TLDR
It is found that the ionicity of the phase affects its electronic bandgap, infrared adsorption and dielectric constants, and that it arises from the different electronic properties of the B2 pairs and B12 clusters and the resultant charge transfer between them.
The interrelation between hardness and compressibility of substances and their structure and thermodynamic properties
A strong correlation relationship has been established between the structure and specific Gibbs free energy of the substance atomization on the one hand, and the substance hardness and volume
Structure and Chemistry of Crystalline Solids
-Introduction. -Classification of Crystals, Point Groups and Space Groups. -Close Packing and the PTOT System. -Structures of The Elements. -Crystal Structures Involving P and 0 Layers. -Crystal
Ionic high-pressure form of elemental boron
TLDR
This corrects the article to show that the H2O2/H2O/O2 balance is determined by a combination of H2A and O2 values, not necessarily reflecting a direct relationship between these values and each other.
...
...