Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395
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Article Pressure-Driven Structural Evolution of Amorphous InN(Elsevier, 2025-02) Durandurdu, MuratThrough constant-pressure ab initio simulations, we have uncovered high-pressure phase transformations in amorphous indium nitride for the first time. Our results reveal a distinct two-step progression under compression. Initially, a polyamorphic transition occurs, where the low-density amorphous (LDA) phase transforms into a high-density amorphous (HDA) phase. This HDA structure remains stable in some pressure range and then crystallization initiates, leading to a rocksalt configuration. Upon decompression, the HDA phase reverts to an amorphous network with a slightly higher density and coordination number than the initial LDA state.Article Citation - WoS: 5Citation - Scopus: 4Densification of Amorphous Boron Under Pressure(Elsevier, 2017-09) Durandurdu, MuratThe densification mechanism of amorphous boron under pressure is investigated using a constant pressure ab initio technique and found to be associated with two consecutive amorphous-to-amorphous phase transformations. Amorphous boron gradually transforms into a high density amorphous phase, followed by a first order phase transformation into another high density amorphous state. The high density amorphous phases of boron are not quenchable to ambient pressure. Most quasimolecular B-12 icosahedra in the model are found to be stable at the highest the theoretical pressure of 280 GPa reached in the present work and thus the phase transformations are principally due to the re-structural arrangements in the parts of the model connecting B-12 icosahedra.Article Citation - WoS: 1Citation - Scopus: 1Amorphous GaN: Polyamorphism and Crystallization at High Pressure(Elsevier, 2024-05) Durandurdu, MuratEmploying constant pressure ab initio simulations, we have shed light on the previously unknown high-pressure behavior of amorphous gallium nitride. Our findings reveal a two-step transformation sequence under pressure. The initial transition involves a polyamorphic transformation from a low-density amorphous (LDA) phase to a high-density amorphous (HDA) phase with an average coordination number of 5.4. Upon pressure release, the HDA state partially reverts to a denser amorphous network with a higher coordination number (4.34) compared to the original LDA phase. Further pressurization triggers the crystallization of the HDA state into a rocksalt structure. Remarkably, the electronic structure of the amorphous forms of GaN exhibits insignificant sensitivity to changes in coordination number, maintaining a band gap of approximately 1.7-2.0 eV across all phases.