Sökning: "density functional theory"

Visar resultat 11 - 15 av 111 uppsatser innehållade orden density functional theory.

  1. 11. Symmetry Analysis of Orbitals in a Plane Wave Basis : A Study on Molecules and Defects in Solids

    Master-uppsats, Linköpings universitet/Teoretisk Fysik

    Författare :William Stenlund; [2022]
    Nyckelord :Point Defect; Divacancy; Symmetry; Group Theory; DFT; Plane Wave; Plane Wave Basis; 4H-SiC;

    Sammanfattning : Modeling and analysing materials with theoretical tools is of great use when finding new systems for applications, for example, semiconductors with point defects can be used for quantum applications, like single photon emitters. One important aspect to consider symmetry, which can yield useful information about the properties of a system. LÄS MER

  3. 12. Time-resolved x-ray diffraction study of longitudinal optical phonons in zincblende semiconductors

    Master-uppsats, Lunds universitet/Atomfysik; Lunds universitet/Fysiska institutionen

    Författare :Lassi Linnala; [2022]
    Nyckelord :femtosecond THz radiation; ultrafast x-ray diffraction; pump-probe; longitudinal optical phonons; zincblende semiconductors; anharmonic decay; density functional perturbation theory; Physics and Astronomy;

    Sammanfattning : Anharmonic decay of longitudinal optical (LO) phonons in zincblende semiconductors is not at present well characterized due to the polar and many-body nature of the problem. Femtosecond THz radiation offers a novel route to this study, as the interaction of this radiation is directly with the phonon lattice and these THz excited phonons do not have enough energy to excite electrons over the band gap. LÄS MER

  4. 13. First Principles Studies Of 2D Magnets

    Kandidat-uppsats,

    Författare :Yahya Fayazi; Linus Jacobsson; Folke Gustafsson; [2022]
    Nyckelord :2D material; ab initio; magnet; Quantum Espresso; Density Functional Theory; DFT; CrCl3; CrBr3; CrI3; 2D material; 2 dimensionella material; två dimensionella material;

    Sammanfattning : The aim of this project is to examine the electric and magneticproperties of three monolayer chromium trihalides when doped withdifferent transitions metals, that is CrXY_6, where X=(Mn,Fe,Co,Ni,V)and Y=(Cl,Br,I). The calculations were made using the software programQuantum Espresso that used density functional theory to solveSchrödinger’s equation. LÄS MER

  5. 14. Teoretisk undersökning av bulkstrukturer av YSZ och en tvillinggräns av t-ZrO2 med DFT

    Kandidat-uppsats, Malmö universitet/Fakulteten för teknik och samhälle (TS)

    Författare :Ali Tayebi; Fanny Andersson; [2022]
    Nyckelord :DFT;

    Sammanfattning : The material yttria-reinforced zirconia (YSZ) is widely used in biomedical applications and is the latest material in dentistry for the production of dental implants such as crowns and bridges. The used concentrations of yttria in zirconia are usually between 3-8 mol% Y2O3 dissolved in the ZrO2 structure, which stabilizes ZrO2 in tetragonal structure at RT. LÄS MER

  7. 15. Study of hole mobility in amorphous polyethylene via kinetic Monte Carlo methods

    Master-uppsats, KTH/Matematik (Avd.)

    Författare :Hannes Aspåker; [2022]
    Nyckelord :;

    Sammanfattning : This thesis presents a study of hole mobility in amorphous polyethylene using kinetic Monte Carlo (KMC) methods together with a novel chain segmentation model developed by Unge and Nilsson, which determines hole localization sites based on torsion angles along the polymer chain. An extension to the KMC algorithm was developed which improves performance by modelinground-trips between strongly interconnected localization sites. LÄS MER