Boron: Another Form

  title={Boron: Another Form},
  author={Robert H. Wentorf},
  pages={49 - 50}
A hitherto undescribed form of boron can be prepared by subjecting ordinary forms of boron to pressures exceeding about 100 kilobars and temperatures between about 1500� to 2000�C. The new form has a density of about 2.52 g/cm3 and yields a characteristic DeBye-Scherrer pattern. No large crystals have been prepared. 
Synthesis of an orthorhombic high pressure boron phase
Abstract The densest boron phase (2.52 g cm-3) was produced as a result of the synthesis under pressures above 9 GPa and temperatures up to ∼1800 °C. The x-ray powder diffraction pattern and the
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
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
Polarized Raman spectroscopy of high-pressure orthorhombic boron phase
We synthesized the single crystals of the orthorhombic (space group Pnnm) boron B28 phase in a multi-anvil press and studied them by means of polarized Raman spectroscopy. Among all possible 42
Superhard phases of simple substances and binary compounds of the B-C-N-O system: from diamond to the latest results (a Review)
The basic known and hypothetic one- and two-element phases of the B-C-N-O system (both superhard phases having diamond and boron structures and precursors to synthesize them) are described. The
Superhard semiconducting optically transparent high pressure phase of boron.
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.
Borides and boranes
The Beta-Rhombohedral Boron Structure
All of the essential features of the structure of beta-rhombohedral boron were described in a recent communication; it is appropriate at mis point to elaborate upon some of the general features of
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
Boron Modifications Produced in an Induction-Coupled Argon Plasma
Most of the small particles of microcrystalline β-rhombohedral boron that quickly transit an argon plasma maintained within a radio-frequency induction-coupled torch emerge as better crystallized spheroids of the same crystalline form and nearly the same size as the starting material.


Direct Conversion of Graphite to Diamond in Static Pressure Apparatus.
At pressures above about 125 kbar and temperatures in the 3000°K range it is found that graphite spontaneously collapses completely to polycrystalline diamond which may be retrieved quantitatively.
Über die Modifikationen des Bors. Versuche zur Einlagerung von Beryllium in das Borgitter
Nach einem Uberblick uber die bisher bekannten Bor-Modifikationen werden Versuche beschrieben, durch gemeinsames Zersetzen von BBr3 BeBr2 am gluhenden Tantaldraht Borkristalle mit eingelagertem
Plenum Press, New York, 1960)
  • J. Am. Chem. Soc. 82,
  • 1960
DeBye-Scherrer Card No. 11-618; see also D. E. Sands and J. L. Hoard
  • J. Am. Chem. Soc
  • 1957
DeCarlo for preparing many DeBye-Scherrer x-ray patterns