Structure and equation of state of tetragonal boron subnitride B50N2

Abstract

New boron subnitride B50N2 has been synthesized by crystallization from the B-BN melt at 5 GPa, and its structure has been refined using Rietveld analysis. B50N2 crystallizes in the tetragonal space group P-4n2 with unit cell parameters a = 8.8181(2) A and c = 5.0427(10) A. Quasi-hydrostatic compression of two boron subnitrides, B50N2 and B13N2, has been studied to 30 GPa at room temperature in a diamond-anvil cell using synchrotron X-ray diffraction. No pressure-induced phase transitions have been observed. A fit of experimental p-V data to the Murnaghan equation of state yielded B50N2 and B13N2 bulk moduli of 167(2) and 205(2) GPa, respectively, with fixed first bulk modulus pressure derivative of 4.0.

References in corpus (5)

• Boron: a Hunt for Superhard Polymorphs
• Superhard Phases of Simple Substances and Binary Compounds of the B-C-N-O System: from Diamond to the Latest Results (a Review)
• Thermodynamic aspects of materials' hardness: prediction of novel superhard high-pressure phases
• Thermoelastic equation of state of boron subphosphide B12P2
• Orthorhombic boron oxide under pressure: in situ study by X-ray diffraction and Raman scattering

Cited by in corpus (7)

• Discovery of new boron-rich chalcogenides: orthorhombic B6X (X = S, Se)
• Phase diagram of the B-BN system at pressures up to 24 GPa: Experimental study and thermodynamic analysis
• Thermal expansion of α-boron and some boron-rich pnictides
• Equation of state of boron subarsenide B12As2 to 47 GPa
• High-pressure synthesis of boron-rich chalcogenides B12S and B12Se
• Equations of state of new boron-rich selenides B${}_6$Se and B${}_{12}$Se
• Thermal expansion of boron subnitrides