Gallium and indium under high pressure

Physical Review Letters

Volumn 85, Issue 1, 2000, Pages 142-145

  Simak, S I ^a   Haussermann U ^b   Ahuja, R ^c   Lidin, S ^b   Johansson, B ^c  

^a CHALMERS UNIVERSITY OF TECHNOLOGY   (Sweden)

^b STOCKHOLM UNIVERSITY   (Sweden)

^c UPPSALA UNIVERSITY   (Sweden)

Author keywords

[No Author keywords available]

Indexed keywords

BAND STRUCTURE; CRYSTAL SYMMETRY; CRYSTALLIZATION; ELECTRONIC DENSITY OF STATES; FERMI LEVEL; GROUND STATE; HIGH PRESSURE EFFECTS; PHASE TRANSITIONS; SEMICONDUCTING GALLIUM; SEMICONDUCTING INDIUM;

BODY CENTERED TETRAGONAL STRUCTURE; FACE CENTERED CUBIC STRUCTURE; LINEAR MUFFIN TIN ORBITAL METHOD; STRUCTURAL TRANSITIONS;

CRYSTAL ATOMIC STRUCTURE;

EID: 0343878210     PISSN: 00319007     EISSN: None     Source Type: Journal    
DOI: 10.1103/PhysRevLett.85.142     Document Type: Article

References (22)

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15. The calculations were based on the local-density approximation (LDA) in the form given by L. Hedin and B. I. Lundqvist, J. Phys. C 4, 2064 (1971). Basis functions, electron densities, and potentials were calculated without any shape approximation. We made use of s, p, and d valence band basis functions for both Ga and In, with 3d pseudocore states for Ga and 4d (and for very high compressions 4p) pseudocore states for In included in the corresponding basis as well. For sampling the irreducible wedge of the Brillouin zone (BZ) we used the special k points with a Gaussian smearing of width 5 to 20 mRy. The extremely small total energy differences considered in the present work required extreme precautions as regards convergence. All necessary tests were carried out. The most crucial parameter turned out to be the number of k-points in the summation over the BZ. For volumes corresponding to the transition regions up to 7408K k-points in the full bet BZ were taken into account.
16. K. Takemura (private communication); W. B. Holzapfel (private communication).
17. K. Takemura (private communication); W. B. Holzapfel (private communication).
18. For calculating the band structures we used a tetragonal body centered (bet) unit cell with the appropriate c/a ratio of √2.
19. It is known that the LDA usually gives rise to a semicore state which is higher in energy compared to experimental data due to the self-interaction. However, our tests treating semicore states as atomiclike and employing a self-interaction corrected (SIC) functional show that the energy vs c/a dependence is qualitatively unaffected.
20. J. K. Burdett, Chemical Bonding in Solids (Oxford University Press, Oxford, 1995).
21. 0) was always kept constant for all c/a at a particular volume.
22. c = 3.38 K) will be considerably enhanced under pressure.