|
| Titre : |
Ab-initio Study of fundamental properties of a cubic perovskite - BiIno3 |
| Type de document : |
document électronique |
| Auteurs : |
Sanaa Abiren, Auteur ; Mohamed Salah Halati, Directeur de thèse |
| Editeur : |
Setif:UFA |
| Année de publication : |
2025 |
| Importance : |
1 vol (80 f.) |
| Format : |
29 cm |
| Langues : |
Anglais (eng) |
| Catégories : |
Thèses & Mémoires:Physique
|
| Mots-clés : |
BiIn????????
PP-PW method
Elastic constants
Electronic properties
Structural properties
Elastic properties and chemical bonding |
| Index. décimale : |
530 - Physique |
| Résumé : |
In this work, we studied the structural, electronic and elastic properties of the cubic perovskite composite BiIn????????. The aim of this work is to know the properties of BiIn???????? in preparation for the possible use of this compound in certain applications and fields. For this purpose, we used the (ab initio) calculation method, based on the density functional theory (DFT) included in CASTEP and integrated with the plane wave method and pseudopotentials (PP-PW), to calculate the cross-correlation potential (Xc), we used the localized density approximation (LDA) as well as the generalized gradient approximation (GGA) in the calculations and found that the lattice constant and compressive modulus obtained are consistent with the theoretical results. The elasticity constants increase with increasing hydrostatic pressure, where we studied a range from 0 GPa to 40 GPa. As for the elastic properties, we calculated the Zener ratio and found that the compound is anisotropic; and more rigid along the crystalline direction [100], The elastic constants fulfilled the stability conditions, which means that our compound is structurally stable. The results of the energy band analysis indicated that the studied compound is an indirect band gap conductor, moreover, by analyzing the density of state spectrum we found that the chemical bonds are a mixture of valence and ionic bonds and that Bi -6p constitutes the majority of the conduction band, according to DOS analysis, while O -2p states practically dominate the valence band. Our results from the study of the physical properties of the BiIn???????? molecule indicate that our compound could be a good substitute (candidate) for lead-containing materials to protect nature from its toxicity . |
| Note de contenu : |
Sommaire
Acknowledgments .................................................................................................................................
Dedication .............................................................................................................................................
The used abbreviations: ........................................................................................................................
Table des matieres : ...............................................................................................................................
Tables list: .............................................................................................................................................
General Introduction ................................................................................................................... a ,b,c
Referenses: ......................................................................................................................................... d
Chapter 1 : Semiconductors: the cubic perovskite family
Semi-conductors and perovskites compounds ...................................................................................... 2
I.1. Introduction ................................................................................................................................... 2
I.2. The semi-conductor ........................................................................................................................ 3
I.2.1. Definition of semi-conductors ..................................................................................................... 3
I.2.2. Physical properties of semiconductors ........................................................................................ 4
I.2.2.1. Fermi level concept ................................................................................................................... 4
â… . 2. 2. 2. Energy Bands ........................................................................................................................ 7
â… . 2. 2. 3. Notion of direct gap and indirect gap .................................................................................... 8
â… . 2. 2. 3. 1. Direct electron transitions .................................................................................................. 8
â… . 2. 2. 3. 2. Indirect electronic transitions ............................................................................................. 8
â… . 2. 2. 4. Principles of Band Structure .................................................................................................. 8
â… . 2. 2. 5. Mobility of Free-Loading Cars ............................................................................................ 10
â… . 2 . 2 . 6 . Intermediate electrical conductivity ................................................................................. 11
â… . 2. 2. 7. Electrical resistivity ............................................................................................................ 12
â… . 2. 2. 8. Hall effect ............................................................................................................................ 12
â… . 2. 2. 9. The photovoltaic effect ........................................................................................................ 13
â… . 2. 2. 10. Optical Absorption ............................................................................................................. 15
â… . 2. 2. 11. Attenuation and absorption coefficients ............................................................................ 16
â… . 2. 2. 12. Refractive index ................................................................................................................. 17
â… . 2. 2. 13. Reflection and transmission coefficient ............................................................................. 18
I.2.3. Chemical properties ................................................................................................................... 19
I.2.3.1.Structural characteristics of semiconductors ........................................................................... 19
I.2.3.1.1.Diamond structure ................................................................................................................. 19
I.2.3.1.2.Zinc blende structure ............................................................................................................. 20
I.2.3.1.3.Wurtzite structure .................................................................................................................. 20
I.2.3.1.4.Structure of sodium chloride (NaCl) ..................................................................................... 21
I.2.3.2.Different types of semiconductors ........................................................................................... 21
I.2.3.2.1.Intrinsic semiconductors ....................................................................................................... 21
I.2.3.2.2.Intrinsic semiconductors ....................................................................................................... 22
I.2.3.3.The Different types of bonds and their influence on structures ............................................... 23
I.2.3.3.1.Covalent Bonding ................................................................................................................. 23
I.2.3.3.2.Ionic Bond ............................................................................................................................. 25
I.2.3.3.3.Ionic-Covalent bonds ............................................................................................................ 25
I.2.3.4.Doping of semiconductors ....................................................................................................... 26
I.2.3.5.The PN junction ....................................................................................................................... 26
I.3.Perovskites .................................................................................................................................... 27
I.3.1.Definition of perovskites ............................................................................................................. 27
I.3.2.Crystal structure of Perovskites .................................................................................................. 28
I.3.3.The process of Perovskite formation requires ............................................................................ 29
I.3.4.Conditions for the stability of the perovskite structure ............................................................... 29
I.3.4.1.Tolerance factor (t) .................................................................................................................. 29
I.3.4.2.The ionic form of the bonds ..................................................................................................... 30
I.3.5.Classification of Perovskites ....................................................................................................... 30
I.3.5.1.Oxide family ............................................................................................................................ 30
I.3.5.2.Halogen family ......................................................................................................................... 32
I.3.6.Applications and properties of some types of perovskites .......................................................... 32
I.4.Conclusion .................................................................................................................................... 34
Chapter 2: The (DFT): Density Functional theory with
(The used approximation ) potential and related accuracy.
II.1. introduction: ............................................................................................................................... 41
II.2. The APW method ....................................................................................................................... 41
II.3. The FP/LAPW method ............................................................................................................... 44
II.3.1. The LAPW Basis functions ..................................................................................................... 44
II.3.2. Semi-core states problem ......................................................................................................... 47
II.3.2.1. Multiple energy windows ..................................................................................................... 47
II.3.2.2. Local orbitals .........................................................................................................................
II.3.2.2.1. LAPW+LO method ........................................................................................................... 48
II.3.2.2.2. APW+lo method ................................................................................................................ 50
II.3.3. The Concept of FP-LAPWmethod .......................................................................................... 51
II.4. TB-mBJ approach (The latest correlation and exchange potential modification)
II.5. Referenses: .................................................................................................................................. 54
Chapter 3: Results and discussions
â…¢ . 1. Introduction .............................................................................................................................. 58
â…¢ . 2 Structural form of the compound BiIn????3 ................................................................................. 58
â…¢.3. Calculation method .................................................................................................................... 60
â…¢ . 4. Results and discussions ............................................................................................................ 60
â…¢ .4. 1. Study of Structural properties: ............................................................................................ 60
â…¢. 4 .2 Elastic properties .................................................................................................................... 63
â…¢. 4 .2.1. Elastic anisotropy study : ................................................................................................... 66
â…¢ . 4 .2.2. Mechanical stability: ........................................................................................................ 67
â…¢. 4 .2.3. Calculation of anisotropic elastic wave velocities: .......................................................... 68
III .4. 2.4. Effect of pressure on the elastic constants of BiIn????3 ........................................................ 69
â…¢ . 4. 3. Electronic Properties ........................................................................................................... 71
Conclusion: ......................................................................................................................................... 76
Références .......................................................................................................................................... 77 |
| Côte titre : |
MAPH/0712 |
Ab-initio Study of fundamental properties of a cubic perovskite - BiIno3 [document électronique] / Sanaa Abiren, Auteur ; Mohamed Salah Halati, Directeur de thèse . - [S.l.] : Setif:UFA, 2025 . - 1 vol (80 f.) ; 29 cm. Langues : Anglais ( eng)
| Catégories : |
Thèses & Mémoires:Physique
|
| Mots-clés : |
BiIn????????
PP-PW method
Elastic constants
Electronic properties
Structural properties
Elastic properties and chemical bonding |
| Index. décimale : |
530 - Physique |
| Résumé : |
In this work, we studied the structural, electronic and elastic properties of the cubic perovskite composite BiIn????????. The aim of this work is to know the properties of BiIn???????? in preparation for the possible use of this compound in certain applications and fields. For this purpose, we used the (ab initio) calculation method, based on the density functional theory (DFT) included in CASTEP and integrated with the plane wave method and pseudopotentials (PP-PW), to calculate the cross-correlation potential (Xc), we used the localized density approximation (LDA) as well as the generalized gradient approximation (GGA) in the calculations and found that the lattice constant and compressive modulus obtained are consistent with the theoretical results. The elasticity constants increase with increasing hydrostatic pressure, where we studied a range from 0 GPa to 40 GPa. As for the elastic properties, we calculated the Zener ratio and found that the compound is anisotropic; and more rigid along the crystalline direction [100], The elastic constants fulfilled the stability conditions, which means that our compound is structurally stable. The results of the energy band analysis indicated that the studied compound is an indirect band gap conductor, moreover, by analyzing the density of state spectrum we found that the chemical bonds are a mixture of valence and ionic bonds and that Bi -6p constitutes the majority of the conduction band, according to DOS analysis, while O -2p states practically dominate the valence band. Our results from the study of the physical properties of the BiIn???????? molecule indicate that our compound could be a good substitute (candidate) for lead-containing materials to protect nature from its toxicity . |
| Note de contenu : |
Sommaire
Acknowledgments .................................................................................................................................
Dedication .............................................................................................................................................
The used abbreviations: ........................................................................................................................
Table des matieres : ...............................................................................................................................
Tables list: .............................................................................................................................................
General Introduction ................................................................................................................... a ,b,c
Referenses: ......................................................................................................................................... d
Chapter 1 : Semiconductors: the cubic perovskite family
Semi-conductors and perovskites compounds ...................................................................................... 2
I.1. Introduction ................................................................................................................................... 2
I.2. The semi-conductor ........................................................................................................................ 3
I.2.1. Definition of semi-conductors ..................................................................................................... 3
I.2.2. Physical properties of semiconductors ........................................................................................ 4
I.2.2.1. Fermi level concept ................................................................................................................... 4
â… . 2. 2. 2. Energy Bands ........................................................................................................................ 7
â… . 2. 2. 3. Notion of direct gap and indirect gap .................................................................................... 8
â… . 2. 2. 3. 1. Direct electron transitions .................................................................................................. 8
â… . 2. 2. 3. 2. Indirect electronic transitions ............................................................................................. 8
â… . 2. 2. 4. Principles of Band Structure .................................................................................................. 8
â… . 2. 2. 5. Mobility of Free-Loading Cars ............................................................................................ 10
â… . 2 . 2 . 6 . Intermediate electrical conductivity ................................................................................. 11
â… . 2. 2. 7. Electrical resistivity ............................................................................................................ 12
â… . 2. 2. 8. Hall effect ............................................................................................................................ 12
â… . 2. 2. 9. The photovoltaic effect ........................................................................................................ 13
â… . 2. 2. 10. Optical Absorption ............................................................................................................. 15
â… . 2. 2. 11. Attenuation and absorption coefficients ............................................................................ 16
â… . 2. 2. 12. Refractive index ................................................................................................................. 17
â… . 2. 2. 13. Reflection and transmission coefficient ............................................................................. 18
I.2.3. Chemical properties ................................................................................................................... 19
I.2.3.1.Structural characteristics of semiconductors ........................................................................... 19
I.2.3.1.1.Diamond structure ................................................................................................................. 19
I.2.3.1.2.Zinc blende structure ............................................................................................................. 20
I.2.3.1.3.Wurtzite structure .................................................................................................................. 20
I.2.3.1.4.Structure of sodium chloride (NaCl) ..................................................................................... 21
I.2.3.2.Different types of semiconductors ........................................................................................... 21
I.2.3.2.1.Intrinsic semiconductors ....................................................................................................... 21
I.2.3.2.2.Intrinsic semiconductors ....................................................................................................... 22
I.2.3.3.The Different types of bonds and their influence on structures ............................................... 23
I.2.3.3.1.Covalent Bonding ................................................................................................................. 23
I.2.3.3.2.Ionic Bond ............................................................................................................................. 25
I.2.3.3.3.Ionic-Covalent bonds ............................................................................................................ 25
I.2.3.4.Doping of semiconductors ....................................................................................................... 26
I.2.3.5.The PN junction ....................................................................................................................... 26
I.3.Perovskites .................................................................................................................................... 27
I.3.1.Definition of perovskites ............................................................................................................. 27
I.3.2.Crystal structure of Perovskites .................................................................................................. 28
I.3.3.The process of Perovskite formation requires ............................................................................ 29
I.3.4.Conditions for the stability of the perovskite structure ............................................................... 29
I.3.4.1.Tolerance factor (t) .................................................................................................................. 29
I.3.4.2.The ionic form of the bonds ..................................................................................................... 30
I.3.5.Classification of Perovskites ....................................................................................................... 30
I.3.5.1.Oxide family ............................................................................................................................ 30
I.3.5.2.Halogen family ......................................................................................................................... 32
I.3.6.Applications and properties of some types of perovskites .......................................................... 32
I.4.Conclusion .................................................................................................................................... 34
Chapter 2: The (DFT): Density Functional theory with
(The used approximation ) potential and related accuracy.
II.1. introduction: ............................................................................................................................... 41
II.2. The APW method ....................................................................................................................... 41
II.3. The FP/LAPW method ............................................................................................................... 44
II.3.1. The LAPW Basis functions ..................................................................................................... 44
II.3.2. Semi-core states problem ......................................................................................................... 47
II.3.2.1. Multiple energy windows ..................................................................................................... 47
II.3.2.2. Local orbitals .........................................................................................................................
II.3.2.2.1. LAPW+LO method ........................................................................................................... 48
II.3.2.2.2. APW+lo method ................................................................................................................ 50
II.3.3. The Concept of FP-LAPWmethod .......................................................................................... 51
II.4. TB-mBJ approach (The latest correlation and exchange potential modification)
II.5. Referenses: .................................................................................................................................. 54
Chapter 3: Results and discussions
â…¢ . 1. Introduction .............................................................................................................................. 58
â…¢ . 2 Structural form of the compound BiIn????3 ................................................................................. 58
â…¢.3. Calculation method .................................................................................................................... 60
â…¢ . 4. Results and discussions ............................................................................................................ 60
â…¢ .4. 1. Study of Structural properties: ............................................................................................ 60
â…¢. 4 .2 Elastic properties .................................................................................................................... 63
â…¢. 4 .2.1. Elastic anisotropy study : ................................................................................................... 66
â…¢ . 4 .2.2. Mechanical stability: ........................................................................................................ 67
â…¢. 4 .2.3. Calculation of anisotropic elastic wave velocities: .......................................................... 68
III .4. 2.4. Effect of pressure on the elastic constants of BiIn????3 ........................................................ 69
â…¢ . 4. 3. Electronic Properties ........................................................................................................... 71
Conclusion: ......................................................................................................................................... 76
Références .......................................................................................................................................... 77 |
| Côte titre : |
MAPH/0712 |
|
530 Physique
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