Electronic and elastic properties of PbS under pressure

High-Pressure Structural Stability and Elasticity of Supercrystals Self-Assembled from Nanocrystals

“…Pressure-induced structural transformations of PbS have been studied extensively for bulk material. ,, The bulk modulus and pressure derivative of PbS obtained from the high-pressure experiments were reported to be B 0 ∼ 51−57 GPa and B 0 ′ ∼ 4.0−4.3, respectively. ,, The high-pressure results obtained for PbS NCs revealed elevated first-order phase transition pressure when compared to the bulk phase, although no definitive calculations have established the size-dependent mechanical properties of the NCs. Qadri et al revealed decreasing slopes of the room temperature P − V data for decreasing NCs sizes, suggesting that the mechanical properties in fact decrease with decreasing NC size …”

“…42,43 Pressure-induced structural transformations of PbS have been studied extensively for bulk material. 64,71,72 The bulk modulus and pressure derivative of PbS obtained from the high-pressure experiments were reported to be B 0 ∼ 51-57 GPa and B 0 0 ∼ 4.0-4.3, respectively. 64,65,72 The high-pressure results obtained for PbS NCs revealed elevated first-order phase transition pressure when compared to the bulk phase, although no definitive calculations have established the size-dependent mechanical properties of the NCs.…”

Characterization of the microstructure in random and textured polycrystals and single crystals by diffraction line profile analysis

“…For example, the elastic anisotropy, i.e. A z = 2c 44 /(c 11 − c 12 ), of PbS is A z ∼ = 0.31 [40]. The corresponding value of the q parameter in Eq.…”

“…The Rwp values varied between 0.35 and 0.55 and the M values were between 1.8 and 3, where the smaller values correspond to the larger dislocation densities in correlation with the screening effect of dislocations [6]. Table 2 The median and variance, m and , of the log-normal size distribution of sub-grains, the area average mean crystallite size, x area , the average dislocation density, , the average density of twin boundaries,ˇand the q parameter values for the dislocation contrast factors, for the three materials, Cu, Cu-10%Zn and Cu-30%Zn at positions of 0 R, (1/2) R and 1 R, respectively [40,41]. Rwp in the last row gives the reliability of the fit, cf.…”

Simulation Mechanical Properties of Lead Sulfur Selenium under Pressure

“…The first-principles calculations presented here were performed by the CASTEP program on the platform of Materials Studio, which is based on density functional theory using a plane-wave basis set for the expansion of the wave functions [15][16][17]. Non-local ultra-soft pseudo-potentials were used to describe the valence electrons.…”