Maregedze, Chris Nhamo2020-02-122020-02-122019https://hdl.handle.net/10539/28874A dissertation submitted to the Faculty of Science, University of Witwatersrand in fulfillment of the requirements for the degree of Master of Science (MSc). School of Physics, University of Witwatersrand, Johannesburg May, 2019An ever-growing interest in transition metal chalcogenide materials due to their intriguing properties has led to extensive investigations of their structural, electronic, optical and thermal properties and their applications as building blocks for optoelectric and thermoelectric devices. Properties of PtS2, PtSe2 and PtTe2 were investigated from first principles DFT calculations. PBE+TS functional had lattice parameters more comparable to experimental volume and were therefore used for further studies. Phonon and elastic constants calculations confirmed dynamical and mechanical stability. Pt was the dominant contributor to acoustic modes and as volume increased from S, Se to Te the frequency dispersion of acoustic modes decreased. Their bulk moduli increased as volume increased. Electronic, optical and thermal properties were explored to ascertain suitability as building blocks for optoelectric and thermoelectric devices. Optical properties illustrated anisotropy within the visible range, 1.6 eV-3.1 eV. Lattice thermal conductivity at 300K in out-of-plane was observed to be much lower compared to in-plane for all the materialsenThesis