Identification of the pressure-induced phase transition of ZnSe with the positron annihilation method
This paper studies the pressure-induced phase transition between zincblende (B3) and NaC1 (B1) structure ZnSe by using the hydrostatic pressure first-principles pseudopotential plane wave method. The energy-volume and enthalpy- pressure curves are employed to estimate the transition pressure. It is...
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Published in | Chinese physics B Vol. 20; no. 10; pp. 452 - 456 |
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Main Authors | , , , , , |
Format | Journal Article |
Language | English |
Published |
IOP Publishing
01.10.2011
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Subjects | |
Online Access | Get full text |
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Summary: | This paper studies the pressure-induced phase transition between zincblende (B3) and NaC1 (B1) structure ZnSe by using the hydrostatic pressure first-principles pseudopotential plane wave method. The energy-volume and enthalpy- pressure curves are employed to estimate the transition pressure. It is found that ZnSe undergoes a first-order phase transition from the B3 structure to the B1 structure at approximately 15 GPa derived from the energy-volume relation and 14 GPa based on deduction from enthalpy pressure data. The pressure-related positron bulk lifetimes of the two ZnSe structures are calculated with the atomic superposition approximation method. In comparison with the 13.4% reduction in volume of ZnSe at the transition pressure, the positron bulk lifetime decreases more significantly and the relative value declines up to 22.3%. The results show that positron annihilation is an effective technique to identify and characterize the first-order phase transition and can give valuable information about changes in micro-scale, such as volume shrinkage and compressibility. |
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Bibliography: | This paper studies the pressure-induced phase transition between zincblende (B3) and NaC1 (B1) structure ZnSe by using the hydrostatic pressure first-principles pseudopotential plane wave method. The energy-volume and enthalpy- pressure curves are employed to estimate the transition pressure. It is found that ZnSe undergoes a first-order phase transition from the B3 structure to the B1 structure at approximately 15 GPa derived from the energy-volume relation and 14 GPa based on deduction from enthalpy pressure data. The pressure-related positron bulk lifetimes of the two ZnSe structures are calculated with the atomic superposition approximation method. In comparison with the 13.4% reduction in volume of ZnSe at the transition pressure, the positron bulk lifetime decreases more significantly and the relative value declines up to 22.3%. The results show that positron annihilation is an effective technique to identify and characterize the first-order phase transition and can give valuable information about changes in micro-scale, such as volume shrinkage and compressibility. high-pressure, phase transition, positron annihilation 11-5639/O4 ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 |
ISSN: | 1674-1056 2058-3834 |
DOI: | 10.1088/1674-1056/20/10/108105 |