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Investigation on structural, mechanical, electronic, vibrational, thermophysical, optic, and hydrogen storage properties of K2CaH4 under pressures from 0 to 15 GPa   
Yazarlar (3)
Çağatay Yamçıçıer
Osmaniye Korkut Ata Üniversitesi, Türkiye
Prof. Dr. Cihan KÜRKÇÜ Prof. Dr. Cihan KÜRKÇÜ
Kırşehir Ahi Evran Üniversitesi, Türkiye
Sümeyra Yamçıçıer
Osmaniye Korkut Ata Üniversitesi, Türkiye
Devamını Göster
Özet
We investigated the physical properties of K₂CaH₄ under 0–15 GPa using first-principles calculations. The lattice parameters are a = b = 4.4148 Å, c = 14.1434 Å, with formation enthalpy −0.4001 eV atom-1 and cohesive energy 2.85 eV atom-1. The elastic constants satisfy the mechanical-stability criteria. Electronic band gaps are wide, decreasing slightly with pressure (3.38 eV at 0 GPa to 3.23 eV at 15 GPa), identifying K₂CaH₄ as an insulator. Phonon dispersions show no imaginary modes up to 10 GPa and the onset of instability at 15 GPa. The Debye temperature rises from 388.04 K (0 GPa) to 419.88 K (10 GPa) and then drops to 352.59 K (15 GPa). Optically, the maximum absorption coefficient reaches 5.59 × 105 cm-1 at 35.58 eV, and peak reflectivity increases to 69%. Hydrogen-storage metrics are a gravimetric capacity of 2.86 wt% and a volumetric capacity of 48.17 gH₂L-1.
Anahtar Kelimeler
Makale Türü Özgün Makale
Makale Alt Türü SSCI, AHCI, SCI, SCI-Exp dergilerinde yayınlanan tam makale
Dergi Adı Chemical Physics
Dergi ISSN 0301-0104 Wos Dergi Scopus Dergi
Dergi Tarandığı Indeksler SCI-Expanded
Dergi Grubu Q2
Makale Dili İngilizce
Basım Tarihi 01-2026
Cilt No 603
Sayfalar 113039 /
DOI Numarası 10.1016/j.chemphys.2025.113039
Makale Linki https://doi.org/10.1016/j.chemphys.2025.113039