High Pressure Study of Structural and Electronic Properties of PbSe

Abstract

High pressure structural phase transition and electronic properties have been investigated using the linear combination of atomic orbitals (LCAO) method with two exchange-correlation approximations, the generalized gradient approximation (GGA) and local density approximation (LDA). The present study shows phase transitions from B1 to B27 and B27 to B2 at 6.24 GPa and 16.39 GPa, respectively. Lattice constant, bulk modulus, and energy gap of pressure-induced PbSe are found to be in good agreement with previous theoretical and experimental results. Variation of electronic band structure with pressure shows direct band gap alongLpoint of the Brillouin zone.

Experimental study of the size-dependent photoluminescence emission of CBD-grown PbSe nanocrystals on glass

“…The transition of the PbSe NCs from the orthorhombic phase to the cubic can be interpreted via the thermodynamic models. The most stable phase of any crystal has minimum free energy [27]. Besides, the minimum enthalpy and the maximum entropy are in favor of minimizing free energy (G(P,T)=H-TS).…”

“…However, due to the temperature dependency of enthalpy and entropy, the interpretation of the phase transition is not straightforward. However, the impact of enthalpy is investigated by GGA and LDA approximations in [27].…”

Ab initio phase diagram of PbSe crystals calculated with the random phase approximation

“…PbX quantum dots are used as versatile building blocks for nanomaterials due to their narrow bandgap and strong interparticle interactions in self-assembled superlattices [2,3]. The bandgap of these materials can be tuned over a wide range by applying external pressure [4][5][6][7][8].…”

“…The pressure-induced structural phase transitions of lead selenide (PbSe), which are the focus of this work, have been studied experimentally [13][14][15][16] and computationally [6,8,[15][16][17][18][19] for several decades. At ambient conditions, PbSe crystallizes in the semiconducting B1 phase (NaCl-type structure, F m3m, No.…”

“…Furthermore, the published DFT results do not present a consistent picture. Depending on the choice of DFT functional, reported transition pressures range from 6.2 to 10.0 GPa for the B1 ↔ B33 transition and from 16.39 to 22.6 GPa for the B33 ↔ B2 transition [8,15,17,18]. These different results directly reflect arXiv:1807.11415v1 [physics.chem-ph] 30 Jul 2018 the problem of choosing the best DFT functional for a given material.…”