Surface charge induced $sp^3$-$sp^2$ transformation: new energy optimization universal mechanism of (4x4) reconstruction of stoichiometric GaN(0001) surface

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Strak, Paweł, Miller, Wolfram, Krukowski, Stanisław
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909216910868480
author Strak, Paweł
Miller, Wolfram
Krukowski, Stanisław
author_facet Strak, Paweł
Miller, Wolfram
Krukowski, Stanisław
contents Ab initio calculations were applied to large size slabs simulations for determination of the properties of the principal structures of the stoichiometric GaN(0001) surface. The results are different from published previously: stoichiometric GaN(0001) surface structure is characterized by mixed structure in which 3/8 top layer Ga atoms remain in standard position with $sp^3$ hybridized bonding while the remaining 5/8 top layer Ga atoms is located in plane of N atoms with $sp^2$ hybridized bonding. This involves charge transfer to the previous one, entailing energy optimization, therefore Ga-s and Ga-p energy difference is driving force for the transition. In large size surfaces Ga atoms create (4 x 4) reconstruction which is additionally stabilized by strain optimization. Heavy doping in the bulk changes $sp^3$ to $sp^2$ ratio thus confirming the charge transfer mechanism of the reconstruction. The charge transfer energy optimization is universal for all surfaces terminated by $sp^3$ bonded atoms.
format Preprint
id arxiv_https___arxiv_org_abs_2401_06531
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Surface charge induced $sp^3$-$sp^2$ transformation: new energy optimization universal mechanism of (4x4) reconstruction of stoichiometric GaN(0001) surface
Strak, Paweł
Miller, Wolfram
Krukowski, Stanisław
Materials Science
Statistical Mechanics
Chemical Physics
Ab initio calculations were applied to large size slabs simulations for determination of the properties of the principal structures of the stoichiometric GaN(0001) surface. The results are different from published previously: stoichiometric GaN(0001) surface structure is characterized by mixed structure in which 3/8 top layer Ga atoms remain in standard position with $sp^3$ hybridized bonding while the remaining 5/8 top layer Ga atoms is located in plane of N atoms with $sp^2$ hybridized bonding. This involves charge transfer to the previous one, entailing energy optimization, therefore Ga-s and Ga-p energy difference is driving force for the transition. In large size surfaces Ga atoms create (4 x 4) reconstruction which is additionally stabilized by strain optimization. Heavy doping in the bulk changes $sp^3$ to $sp^2$ ratio thus confirming the charge transfer mechanism of the reconstruction. The charge transfer energy optimization is universal for all surfaces terminated by $sp^3$ bonded atoms.
title Surface charge induced $sp^3$-$sp^2$ transformation: new energy optimization universal mechanism of (4x4) reconstruction of stoichiometric GaN(0001) surface
topic Materials Science
Statistical Mechanics
Chemical Physics
url https://arxiv.org/abs/2401.06531