Joint experimental and theoretical study of PbGaS under compression.

The effect of pressure on the structural, vibrational, and optical properties of lead thiogallate, PbGaS, crystallizing under room conditions in the orthorhombic EuGaS-type structure (space group ), is investigated. The results from X-ray diffraction, Raman scattering, and optical-absorption measurements at a high pressure beyond 20 GPa are reported and compared not only to calculations, but also to the related compounds α'-GaS, CdGaS, and HgGaS. Evidence of a partially reversible pressure-induced decomposition of PbGaS into a mixture of PbGaS and GaS above 15 GPa is reported.

Unveiling the role of the lone electron pair in sesquioxides at high pressure: compressibility of β-SbO.

The structural, vibrational and electronic properties of the compressed β-Sb2O3 polymorph, a.k.a.

Characterization and Decomposition of the Natural van der Waals SnSbTe under Compression.

High pressure X-ray diffraction, Raman scattering, and electrical measurements, together with theoretical calculations, which include the analysis of the topological electron density and electronic localization function, evidence the presence of an isostructural phase transition around 2 GPa, a Fermi resonance around 3.5 GPa, and a pressure-induced decomposition of SnSbTe into the high-pressure phases of its parent binary compounds (α-SbTe and SnTe) above 7 GPa. The internal polyhedral compressibility, the behavior of the Raman-active modes, the electrical behavior, and the nature of its different bonds under compression have been discussed and compared with their parent binary compounds and with related ternary materials.

Structural and Lattice-Dynamical Properties of TbO under Compression: A Comparative Study with Rare Earth and Related Sesquioxides.

We report a joint experimental and theoretical investigation of the high pressure structural and vibrational properties of terbium sesquioxide (TbO). Powder X-ray diffraction and Raman scattering measurements show that cubic 3̅ (C-type) TbO undergoes two phase transitions up to 25 GPa. We observe a first irreversible reconstructive transition to the monoclinic 2/ (B-type) phase at ∼7 GPa and a subsequent reversible displacive transition from the monoclinic to the trigonal 3̅1 (A-type) phase at ∼1 GPa.

Orpiment under compression: metavalent bonding at high pressure.

We report a joint experimental and theoretical study of the structural, vibrational, and electronic properties of layered monoclinic arsenic sulfide crystals (α-AsS), aka mineral orpiment, under compression. X-ray diffraction and Raman scattering measurements performed on orpiment samples at high pressure and combined with ab initio calculations have allowed us to determine the equation of state and the tentative assignment of the symmetry of many Raman-active modes of orpiment. From our results, we conclude that no first-order phase transition occurs up to 25 GPa at room temperature; however, compression leads to an isostructural phase transition above 20 GPa.

Pressure-Driven Isostructural Phase Transition in InNbO: In Situ Experimental and Theoretical Investigations.

The high-pressure behavior of technologically important visible-light photocatalytic semiconductor InNbO, adopting a monoclinic wolframite-type structure at ambient conditions, was investigated using synchrotron-based X-ray diffraction, Raman spectroscopic measurements, and first-principles calculations. The experimental results indicate the occurrence of a pressure-induced isostructural phase transition in the studied compound beyond 10.8 GPa.