A first-principle study of Os-based compounds: Electronic structure and vibrational properties


Arikan N., Ornek O., Charifi Z., Baaziz H., Ugur Ş., UĞUR G.

JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS, ss.121-127, 2016 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Basım Tarihi: 2016
  • Doi Numarası: 10.1016/j.jpcs.2016.05.009
  • Dergi Adı: JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.121-127
  • Anahtar Kelimeler: DFT, Elastic constants, Ductility, Intermetallic alloys, Specific heat capacity, PHASE-STABILITY, HF-OS, ALLOYS, ZR, TI, METALS, TM, SC, TEMPERATURE, ENTHALPIES
  • Gazi Üniversitesi Adresli: Evet

Özet

The electronic structure, elastic, and phonon properties of OsM (M=Hf, Ti, Y and Zr) compounds are studied using first-principles calculations. Elastic constants of OsY and specific heat capacity of OsM (M=Hf, Ti, Y, and Zr) are reported for the first time. The predicted equilibrium lattice constants are in excellent agreement with experiment. The calculated values of bulk moduli are considerably high but are much smaller than that of Osmium, which is around 400 GPa. The phase stability of the OsM (M=Hf, Ti, Y and Zr) compounds were studied by DOS calculations and the results suggest that OsY is unstable in the B2 phase. The brittleness and ductility properties of OsM (M=Hf, Ti, Y and Zr) are determined. OsM (M=Hf, Ti, Y and Zr) compounds are predicted to be ductile materials. The electronic structure and phonon frequency curves of OsM (M=Hf, Ti, Y and Zr) compounds are obtained. The position of Fermi level of these systems was calculated and discussed in terms of the pseudo gaps. The finite and small DOS at the Fermi level 0.335, 0.375, 1.063, and 0.383 electrons/eV for OsHf, OsTi, OsY, and OsZr, respectively, suggest that OsM (M=Hf, Ti, Y and Zr) compounds are weak metals. (C) 2016 Elsevier Ltd. All rights reserved.