Search

The evolution of crystal structure and the ground state properties of Fe2B and FeB have been studied by performing high pressure X-ray diffraction up to a pressure of ∼24 GPa and temperature dependent (4.2–300 K range) high-pressure resistivity measurements up to ∼ 2 GPa. While a pressure induced reversible structural phase transition from tetragonal to orthorhombic structure is observed at ∼6.3 GPa in Fe2B, FeB has been found to be stable in its orthorhombic phase up to the pressure of 24 GPa. In the case of Fe2B, both parent and daughter phases coexist beyond the transition pressure. The bulk modulus of FeB and Fe2B (tetragonal) have been found to be 248 GPa and 235 GPa respectively. First principle electronic structure calculations have been performed using the present experimental inputs and the calculated ground state properties agree quite well with the major findings of the experiments. Debye temperature extracted from the analysis of low temperature resistivity data is observed to decrease with pressure indicating softening of phonons in both the systems.

The evolution of crystal structure and the ground state properties of Fe2B and FeB have been studied by performing high pressure X-ray diffraction up to a pressure of ∼24 GPa and temperature dependent (4.2–300 K range) high-pressure resistivity measurements up to ∼ 2 GPa. While a pressure induced reversible structural phase transition from tetragonal to orthorhombic structure is observed at ∼6.3 GPa in Fe2B, FeB has been found to be stable in its orthorhombic phase up to the pressure of 24 GPa. In the case of Fe2B, both parent and daughter phases coexist beyond the transition pressure. The bulk modulus of FeB and Fe2B (tetragonal) have been found to be 248 GPa and 235 GPa respectively. First principle electronic structure calculations have been performed using the present experimental inputs and the calculated ground state properties agree quite well with the major findings of the experiments. Debye temperature extracted from the analysis of low temperature resistivity data is observed to decrease with pressure indicating softening of phonons in both the systems.

The evolution of crystal structure and the ground state properties of Fe2B and FeB have been studied by performing high pressure X-ray diffraction up to a pressure of ∼24 GPa and temperature dependent (4.2–300 K range) high-pressure resistivity measurements up to ∼ 2 GPa. While a pressure induced reversible structural phase transition from tetragonal to orthorhombic structure is observed at ∼6.3 GPa in Fe2B, FeB has been found to be stable in its orthorhombic phase up to the pressure of 24 GPa. In the case of Fe2B, both parent and daughter phases coexist beyond the transition pressure. The bulk modulus of FeB and Fe2B (tetragonal) have been found to be 248 GPa and 235 GPa respectively. First principle electronic structure calculations have been performed using the present experimental inputs and the calculated ground state properties agree quite well with the major findings of the experiments. Debye temperature extracted from the analysis of low temperature resistivity data is observed to decrease with pressure indicating softening of phonons in both the systems.

High pressure structural stability studies were carried out on YGa2 (AlB2 type structure at NTP, space group P6/mmm) up to a pressure of ~35 GPa using both laboratory based rotating anode and synchrotron X-ray sources. An isostructural transition with reduced c/a ratio, was observed at ~6 GPa and above ~17.5 GPa, the compound transformed to orthorhombic structure. Bulk modulus B0 for the parent and high pressure phases were estimated using Birch–Murnaghan and modified Birch–Murnaghan equation of state. Electronic structure calculations based on projector augmented wave method confirms the experimentally observed two high pressure structural transitions. The calculations also reveal that the ‘Ga’ networks remains as two dimensional in the high pressure isostructural phase, whereas the orthorhombic phase involves three dimensional networks of ‘Ga’ atoms interconnected by strong covalent bonds.

High pressure structural stability studies were carried out on YGa2 (AlB2 type structure at NTP, space group P6/mmm) up to a pressure of ~35 GPa using both laboratory based rotating anode and synchrotron X-ray sources. An isostructural transition with reduced c/a ratio, was observed at ~6 GPa and above ~17.5 GPa, the compound transformed to orthorhombic structure. Bulk modulus B0 for the parent and high pressure phases were estimated using Birch–Murnaghan and modified Birch–Murnaghan equation of state. Electronic structure calculations based on projector augmented wave method confirms the experimentally observed two high pressure structural transitions. The calculations also reveal that the ‘Ga’ networks remains as two dimensional in the high pressure isostructural phase, whereas the orthorhombic phase involves three dimensional networks of ‘Ga’ atoms interconnected by strong covalent bonds.

High pressure structural stability studies were carried out on YGa2 (AlB2 type structure at NTP, space group P6/mmm) up to a pressure of ~35 GPa using both laboratory based rotating anode and synchrotron X-ray sources. An isostructural transition with reduced c/a ratio, was observed at ~6 GPa and above ~17.5 GPa, the compound transformed to orthorhombic structure. Bulk modulus B0 for the parent and high pressure phases were estimated using Birch–Murnaghan and modified Birch–Murnaghan equation of state. Electronic structure calculations based on projector augmented wave method confirms the experimentally observed two high pressure structural transitions. The calculations also reveal that the ‘Ga’ networks remains as two dimensional in the high pressure isostructural phase, whereas the orthorhombic phase involves three dimensional networks of ‘Ga’ atoms interconnected by strong covalent bonds.