TY  - JOUR
AU  - Zagorac, Dejan
AU  - Buyer, Constantin
AU  - Zagorac, Jelena
AU  - Škundrić, Tamara
AU  - Schön, Christian J.
AU  - Schleid, Thomas
PY  - 2024
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12879
AB  - LaFSe and LaFS materials have shown great potential for various optoelectronic applications, such as photovoltaics, light-emitting diodes, and photodetectors. Mixed LaFSe/LaFS compounds have been synthesized through high-temperature experiments. The introduction of sulfur into LaFSe causes distortion in the crystal lattice, leading to changes in the unit cell. A new algorithm is presented that keeps the symmetries of the mixed LaFSe/LaFS phases, and it is combined with ab initio structure optimization in order to efficiently generate and compute models for solid solution-type compounds. There is good agreement between experimental and theoretical data, and additional predicted structures under extreme conditions in various lanthanoid fluoride selenides/sulfides have been introduced. The substitution of selenium for sulfur within the LaFSe lattice can result in some unusual electronic properties, including changes in the size of the band gap, the character of the gap, and the electronic structure of the material.
T2  - Crystal Growth & Design
T1  - Band-Gap Engineering and Unusual Behavior of Electronic Properties during Anion Substitution of Sulfur in LaFSe
VL  - 24
IS  - 4
SP  - 1648
EP  - 1657
DO  - 10.1021/acs.cgd.3c01291
ER  - 

@article{
author = "Zagorac, Dejan and Buyer, Constantin and Zagorac, Jelena and Škundrić, Tamara and Schön, Christian J. and Schleid, Thomas",
year = "2024",
abstract = "LaFSe and LaFS materials have shown great potential for various optoelectronic applications, such as photovoltaics, light-emitting diodes, and photodetectors. Mixed LaFSe/LaFS compounds have been synthesized through high-temperature experiments. The introduction of sulfur into LaFSe causes distortion in the crystal lattice, leading to changes in the unit cell. A new algorithm is presented that keeps the symmetries of the mixed LaFSe/LaFS phases, and it is combined with ab initio structure optimization in order to efficiently generate and compute models for solid solution-type compounds. There is good agreement between experimental and theoretical data, and additional predicted structures under extreme conditions in various lanthanoid fluoride selenides/sulfides have been introduced. The substitution of selenium for sulfur within the LaFSe lattice can result in some unusual electronic properties, including changes in the size of the band gap, the character of the gap, and the electronic structure of the material.",
journal = "Crystal Growth & Design",
title = "Band-Gap Engineering and Unusual Behavior of Electronic Properties during Anion Substitution of Sulfur in LaFSe",
volume = "24",
number = "4",
pages = "1648-1657",
doi = "10.1021/acs.cgd.3c01291"
}

Zagorac, D., Buyer, C., Zagorac, J., Škundrić, T., Schön, C. J.,& Schleid, T.. (2024). Band-Gap Engineering and Unusual Behavior of Electronic Properties during Anion Substitution of Sulfur in LaFSe. in Crystal Growth & Design, 24(4), 1648-1657.
https://doi.org/10.1021/acs.cgd.3c01291

Zagorac D, Buyer C, Zagorac J, Škundrić T, Schön CJ, Schleid T. Band-Gap Engineering and Unusual Behavior of Electronic Properties during Anion Substitution of Sulfur in LaFSe. in Crystal Growth & Design. 2024;24(4):1648-1657.
doi:10.1021/acs.cgd.3c01291 .

Zagorac, Dejan, Buyer, Constantin, Zagorac, Jelena, Škundrić, Tamara, Schön, Christian J., Schleid, Thomas, "Band-Gap Engineering and Unusual Behavior of Electronic Properties during Anion Substitution of Sulfur in LaFSe" in Crystal Growth & Design, 24, no. 4 (2024):1648-1657,
https://doi.org/10.1021/acs.cgd.3c01291 . .

TY  - CONF
AU  - Zagorac, Dejan
AU  - Zagorac, Jelena
AU  - Đukić, Miloš B.
AU  - Bal, Burak
AU  - Schön, Christian J.
PY  - 2024
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12933
AB  - Since their discovery, iron and hydrogen have been two of the most interesting elements in scientific research, with a variety of known and postulated compounds and applications. Of special interest in materials engineering is the stability of such materials, where hydrogen embrittlement has gained particular importance in recent years. Here, we present the results for the Fe-H system. In the past, most of the work on iron hydrides has been focused on hydrogen-rich compounds since they have a variety of interesting properties at extreme conditions (e.g. superconductivity). However, we present the first atomistic study of an iron-rich Fe4H compound which has been predicted using a combination of data mining and quantum mechanical calculations. Novel structures have been discovered in the Fe4H chemical system for possible experimental synthesis at the atomistic level.
C3  - Procedia Structural Integrity
T1  - Data-driven discovery and DFT modeling of Fe4H on the atomistic level
VL  - 54
SP  - 446
EP  - 452
DO  - 10.1016/j.prostr.2024.01.105
ER  - 

@conference{
author = "Zagorac, Dejan and Zagorac, Jelena and Đukić, Miloš B. and Bal, Burak and Schön, Christian J.",
year = "2024",
abstract = "Since their discovery, iron and hydrogen have been two of the most interesting elements in scientific research, with a variety of known and postulated compounds and applications. Of special interest in materials engineering is the stability of such materials, where hydrogen embrittlement has gained particular importance in recent years. Here, we present the results for the Fe-H system. In the past, most of the work on iron hydrides has been focused on hydrogen-rich compounds since they have a variety of interesting properties at extreme conditions (e.g. superconductivity). However, we present the first atomistic study of an iron-rich Fe4H compound which has been predicted using a combination of data mining and quantum mechanical calculations. Novel structures have been discovered in the Fe4H chemical system for possible experimental synthesis at the atomistic level.",
journal = "Procedia Structural Integrity",
title = "Data-driven discovery and DFT modeling of Fe4H on the atomistic level",
volume = "54",
pages = "446-452",
doi = "10.1016/j.prostr.2024.01.105"
}

Zagorac, D., Zagorac, J., Đukić, M. B., Bal, B.,& Schön, C. J.. (2024). Data-driven discovery and DFT modeling of Fe4H on the atomistic level. in Procedia Structural Integrity, 54, 446-452.
https://doi.org/10.1016/j.prostr.2024.01.105

Zagorac D, Zagorac J, Đukić MB, Bal B, Schön CJ. Data-driven discovery and DFT modeling of Fe4H on the atomistic level. in Procedia Structural Integrity. 2024;54:446-452.
doi:10.1016/j.prostr.2024.01.105 .

Zagorac, Dejan, Zagorac, Jelena, Đukić, Miloš B., Bal, Burak, Schön, Christian J., "Data-driven discovery and DFT modeling of Fe4H on the atomistic level" in Procedia Structural Integrity, 54 (2024):446-452,
https://doi.org/10.1016/j.prostr.2024.01.105 . .

TY  - JOUR
AU  - Fischer, Dieter
AU  - Zagorac, Dejan
AU  - Schön, Christian J.
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/11548
AB  - Zinc oxide shows unique properties which are evident in a wide range of applications: as a transparent conducting oxide, wide-bandgap semiconductor, and piezoelectric device. The starting point for understanding the origin of these properties are the subtle details of the crystal structure of ZnO, and thus elucidating its formation process is essential. The in-situ characterization of films deposited at various temperatures provides an important contribution in this regard, especially since this study reports on ZnO film deposition below room temperature down to -240 ◦C. Systematic investigations on nanocrystalline ZnO films as function of the deposition temperature reveal structural disorders caused by the irregular occupation of oxygen tetrahedra forming dioxygen species in zinc oxide. Three distinct material ranges are identified in the range of deposition temperatures between -240 and 300 ◦C. The most surprising observations are the segregation of zinc next to ZnO particles for films deposited at room temperature and the disappearance of the Raman bands of the ZnO lattice for those deposited above 100 ◦C. On both ends of the investigated deposition temperature scale transparent colorless films are obtained, which form a random frozen solid at low temperatures as well as a highly disordered film at high temperatures. The deposits at -80 ◦C are yellow in color, indicating the presence of superoxide ions. This wide variety in the properties of ZnO is enabled by the high flexibility of the wurtzite structure, which tolerates huge distance variations. This observation and the results presented open up important insights into the behavior of zinc oxide.
T2  - Thin Solid Films
T1  - Fundamental insight into the formation of the zinc oxide crystal structure
VL  - 782
SP  - 140017
DO  - 10.1016/j.tsf.2023.140017
ER  - 

@article{
author = "Fischer, Dieter and Zagorac, Dejan and Schön, Christian J.",
year = "2023",
abstract = "Zinc oxide shows unique properties which are evident in a wide range of applications: as a transparent conducting oxide, wide-bandgap semiconductor, and piezoelectric device. The starting point for understanding the origin of these properties are the subtle details of the crystal structure of ZnO, and thus elucidating its formation process is essential. The in-situ characterization of films deposited at various temperatures provides an important contribution in this regard, especially since this study reports on ZnO film deposition below room temperature down to -240 ◦C. Systematic investigations on nanocrystalline ZnO films as function of the deposition temperature reveal structural disorders caused by the irregular occupation of oxygen tetrahedra forming dioxygen species in zinc oxide. Three distinct material ranges are identified in the range of deposition temperatures between -240 and 300 ◦C. The most surprising observations are the segregation of zinc next to ZnO particles for films deposited at room temperature and the disappearance of the Raman bands of the ZnO lattice for those deposited above 100 ◦C. On both ends of the investigated deposition temperature scale transparent colorless films are obtained, which form a random frozen solid at low temperatures as well as a highly disordered film at high temperatures. The deposits at -80 ◦C are yellow in color, indicating the presence of superoxide ions. This wide variety in the properties of ZnO is enabled by the high flexibility of the wurtzite structure, which tolerates huge distance variations. This observation and the results presented open up important insights into the behavior of zinc oxide.",
journal = "Thin Solid Films",
title = "Fundamental insight into the formation of the zinc oxide crystal structure",
volume = "782",
pages = "140017",
doi = "10.1016/j.tsf.2023.140017"
}

Fischer, D., Zagorac, D.,& Schön, C. J.. (2023). Fundamental insight into the formation of the zinc oxide crystal structure. in Thin Solid Films, 782, 140017.
https://doi.org/10.1016/j.tsf.2023.140017

Fischer D, Zagorac D, Schön CJ. Fundamental insight into the formation of the zinc oxide crystal structure. in Thin Solid Films. 2023;782:140017.
doi:10.1016/j.tsf.2023.140017 .

Fischer, Dieter, Zagorac, Dejan, Schön, Christian J., "Fundamental insight into the formation of the zinc oxide crystal structure" in Thin Solid Films, 782 (2023):140017,
https://doi.org/10.1016/j.tsf.2023.140017 . .

TY  - JOUR
AU  - Fischer, Dieter
AU  - Zagorac, Dejan
AU  - Schön, Christian J.
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10419
AB  - Zinc oxide exhibits unique properties that are reflected in a wide variety of applications, particularly in the field of transparent, conductive films. However, less attention has been paid to their color. Here, we present the synthesis of yellow-gray ZnO films at room temperature by femtosecond pulsed laser deposition. In situ Raman investigations of these polycrystalline ZnO films reveal the existence of superoxide ions, O2−, in zinc oxide, which are responsible for the yellow color, and are also detected in ZnO powder and single crystals. In addition, further dioxygen species are identified in the samples, including the O2-molecule. The negative charge excess caused by the dioxygen species creates metallic zinc as a byproduct. Structural analysis reveals an unforced realization of the dioxygen species in the ZnO lattice. Density functional theory (DFT) calculations support the assumed structural displacements as well as the observed, unexpected Raman bands. These results open up completely new insights into the behavior of ZnO.
T2  - Journal of Raman Spectroscopy
T1  - The presence of superoxide ions and related dioxygen species in zinc oxide—A structural characterization by in situ Raman spectroscopy
VL  - n/a
IS  - n/a
DO  - 10.1002/jrs.6441
ER  - 

@article{
author = "Fischer, Dieter and Zagorac, Dejan and Schön, Christian J.",
year = "2022",
abstract = "Zinc oxide exhibits unique properties that are reflected in a wide variety of applications, particularly in the field of transparent, conductive films. However, less attention has been paid to their color. Here, we present the synthesis of yellow-gray ZnO films at room temperature by femtosecond pulsed laser deposition. In situ Raman investigations of these polycrystalline ZnO films reveal the existence of superoxide ions, O2−, in zinc oxide, which are responsible for the yellow color, and are also detected in ZnO powder and single crystals. In addition, further dioxygen species are identified in the samples, including the O2-molecule. The negative charge excess caused by the dioxygen species creates metallic zinc as a byproduct. Structural analysis reveals an unforced realization of the dioxygen species in the ZnO lattice. Density functional theory (DFT) calculations support the assumed structural displacements as well as the observed, unexpected Raman bands. These results open up completely new insights into the behavior of ZnO.",
journal = "Journal of Raman Spectroscopy",
title = "The presence of superoxide ions and related dioxygen species in zinc oxide—A structural characterization by in situ Raman spectroscopy",
volume = "n/a",
number = "n/a",
doi = "10.1002/jrs.6441"
}

Fischer, D., Zagorac, D.,& Schön, C. J.. (2022). The presence of superoxide ions and related dioxygen species in zinc oxide—A structural characterization by in situ Raman spectroscopy. in Journal of Raman Spectroscopy, n/a(n/a).
https://doi.org/10.1002/jrs.6441

Fischer D, Zagorac D, Schön CJ. The presence of superoxide ions and related dioxygen species in zinc oxide—A structural characterization by in situ Raman spectroscopy. in Journal of Raman Spectroscopy. 2022;n/a(n/a).
doi:10.1002/jrs.6441 .

Fischer, Dieter, Zagorac, Dejan, Schön, Christian J., "The presence of superoxide ions and related dioxygen species in zinc oxide—A structural characterization by in situ Raman spectroscopy" in Journal of Raman Spectroscopy, n/a, no. n/a (2022),
https://doi.org/10.1002/jrs.6441 . .

TY  - CHAP
AU  - Zagorac, Dejan
AU  - Schön, Christian J.
AU  - Wales, David J.
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10304
AB  - This book chapter provides a comprehensive overview of research on the energy landscapes of zinc oxide (ZnO), one of the most investigated materials, due to its great variety of technological and industrial applications. Thus, not only crystalline and bulk ZnO – both pure and doped – but also ZnO surfaces, monolayers, nanotubes, clusters, cluster-assembled materials, and ZnO nanostructures and nanomaterials in general are of great interest. In order to fully explore the energy landscape of ZnO on all length scales ranging from bulk, layers, and nanotubes to clusters, a broad range of landscape exploration methods has been employed in the literature, including, e.g., global optimisation for structure prediction using empirical potentials, local optimisation at the ab initio level, and the prescribed path algorithm, the threshold algorithm, and metashooting for the study of the barrier structures and transition regions of the landscapes of ZnO. As examples of such landscape investigations, doped and pure crystalline ZnO, as well as ZnO surfaces, clusters, and nanotubes will be discussed.
T2  - Frontiers of Nanoscience
T1  - Chapter 8 - Energy landscapes of pure and doped ZnO: from bulk crystals to nanostructures
VL  - 21
SP  - 151
EP  - 193
DO  - 10.1016/B978-0-12-824406-7.00015-4
ER  - 

@inbook{
author = "Zagorac, Dejan and Schön, Christian J. and Wales, David J.",
year = "2022",
abstract = "This book chapter provides a comprehensive overview of research on the energy landscapes of zinc oxide (ZnO), one of the most investigated materials, due to its great variety of technological and industrial applications. Thus, not only crystalline and bulk ZnO – both pure and doped – but also ZnO surfaces, monolayers, nanotubes, clusters, cluster-assembled materials, and ZnO nanostructures and nanomaterials in general are of great interest. In order to fully explore the energy landscape of ZnO on all length scales ranging from bulk, layers, and nanotubes to clusters, a broad range of landscape exploration methods has been employed in the literature, including, e.g., global optimisation for structure prediction using empirical potentials, local optimisation at the ab initio level, and the prescribed path algorithm, the threshold algorithm, and metashooting for the study of the barrier structures and transition regions of the landscapes of ZnO. As examples of such landscape investigations, doped and pure crystalline ZnO, as well as ZnO surfaces, clusters, and nanotubes will be discussed.",
journal = "Frontiers of Nanoscience",
booktitle = "Chapter 8 - Energy landscapes of pure and doped ZnO: from bulk crystals to nanostructures",
volume = "21",
pages = "151-193",
doi = "10.1016/B978-0-12-824406-7.00015-4"
}

Zagorac, D., Schön, C. J.,& Wales, D. J.. (2022). Chapter 8 - Energy landscapes of pure and doped ZnO: from bulk crystals to nanostructures. in Frontiers of Nanoscience, 21, 151-193.
https://doi.org/10.1016/B978-0-12-824406-7.00015-4

Zagorac D, Schön CJ, Wales DJ. Chapter 8 - Energy landscapes of pure and doped ZnO: from bulk crystals to nanostructures. in Frontiers of Nanoscience. 2022;21:151-193.
doi:10.1016/B978-0-12-824406-7.00015-4 .

Zagorac, Dejan, Schön, Christian J., Wales, David J., "Chapter 8 - Energy landscapes of pure and doped ZnO: from bulk crystals to nanostructures" in Frontiers of Nanoscience, 21 (2022):151-193,
https://doi.org/10.1016/B978-0-12-824406-7.00015-4 . .