Hidrojen depolama malzemeleri için MgH2'nin yapısal ve elektronik özellikleri

Bu çalışmada, ab-initio tekniği kullanılarak MgH2’nin yüksek basınç etkisi altındaki davranışı araştırıldı. Siesta programı ile yürütülen simülasyonlar boyunca MgH2’nin bir yüksek basınç fazına rastlandı. Bu faz, Pnnm olarak belirlendi. Bu çalışmada elde edilen faz geçişlerinin deneysel sonuçlarla uyumunu araştırmak için toplam enerji ve entalpi hesaplamaları yapıldı. Bu hesaplamalar sonucu faz değişiminin 6 GPa civarında gerçekleştiği sonucuna varıldı. Bu sonucun literatür ile uyum içinde olduğu görüldü. Ayrıca MgH2’nin elektronik özellikleri de incelendi. MgH2’nin elde edilen her iki fazı için de yarı iletken özellikte olduğu görüldü.

Anahtar Kelimeler:

Yapısal Faz Geçişi, DFT, Ab-initio moleküler dinamik

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