Hidrojen depolama malzemeleri için MgH2'nin yapısal ve elektronik özellikleri

Yıl 2018, Cilt: 6 Sayı: 2, 451 - 461, 30.06.2018

Cihan Kürkçü Ziya Merdan

https://doi.org/10.29109/http-gujsc-gazi-edu-tr.371285

Cited By: 1

Öz

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

Kaynakça

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