Hidrojen depolama malzemeleri için MgH2'nin yapısal ve elektronik özellikleri

Bu çalışmada, ab-initio tekniği kullanılarak MgH2’nin yüksek basınç etkisi altındaki davranışı40 GPa’ya kadar araştırıldı. Siesta programı ile yürütülen simulasyonlar boyunca MgH2’nin 16GPa’da bir yüksek basınç fazına rastlandı. Bu faz, Pnnm olarak belirlendi. Bu çalışmada eldeedilen faz geçişlerinin deneysel sonuçlarla uyumunu araştırmak için toplam enerji ve entalpihesaplamaları yapıldı. Bu hesaplamalar sonucu faz değişiminin 6 GPa civarında gerçekleştiğisonucuna varıldı. Bu sonucun literatür ile uyum içinde olduğu görüldü. Ayrıca MgH2’ninelektronik özellikleri de incelendi. MgH2’nin elde edilen her iki fazı için de yarı iletkenözellikte olduğu görüldü.

Structural and electronic properties of MgH2 for hydrogen storage materials

In this study, the behavior of MgH2 under high pressure effect was investigated using ab-initio technique up to 40 GPa. During the simulations conducted with the Siesta program, a high pressure phase of MgH2 was found at 16 GPa. This phase was identified as Pnnm. Total energy and enthalpy calculations were carried out to investigate the correspondence of the phase transitions obtained in this study with the experimental results. These calculations are the result of a phase change of around 6 GPa. This result was found to be in accordance with the literature. We also studied the electronic properties of MgH2 . Both phases of MgH2 were found to be semiconducting.

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