Investigation on Structural, Elastic, Electronic and Vibrational Properties of LiTiAl Half-Heusler Compound Using First Principles Methods

Year 2017, Volume: 38 Issue: 2, 312 - 320, 24.04.2017

Yeşim Moğulkoç , Yasemin Öztekin Çiftçi

https://doi.org/10.17776/cumuscij.296598

Cited By: 4

Abstract

Heusler
alloys are particularly noticeable in spintronics and thermoelectric
applications. The researches on new and better thermoelectric materials are
increasing rapidly due to the energy crisis and environmental pollution which
are frequently discussed in recent times. Thermoelectric materials are seen as
potential ways to solve these problems. Half-Heusler materials are considered
thermoelectric materials due to their large temperature stability. Typically, half-Heusler crystallizes in a face-centered cubic structure
with alloys  space group (No.216). In this study, the structural, elastic, electronic and vibrational
properties of the Li-based LiTiAl compound with 8 electrons in the primitive
cell were investigated using the VASP package program using the first
principles methods. The 700 eV cutoff energy and 15x15x15 k-points were used in
calculations. The lattice constant has been calculated as 6.191Å. The obtained
structural parameteres are convenient with the results of literature. Band structures, total and partial density
states graphs are drawn as electronic properties. From these calculations, the
band gap of this compound was found to be 9.55 meV. Elastic constants were
calculated from stress-strain rate. The calculated elastic constants show that
this compound is mechanically stable. Phonon frequencies are calculated and the
structure is found dynamically stable.

Keywords

LiTiAl, Half-Heusler, Vibrational properties, DFT, GGA-PBE.

LiTiAl Yarı-Heusler Alaşımının Yapısal, Elastik, Elektronik ve Titreşimsel Özelliklerinin İlk İlkeler Yöntemleri Kullanılarak İncelenmesi

Abstract

Heusler alaşımları özellikle spintronik ve
termoelektrik uygulamalarda önemli ölçüde dikkat çekmektedir. Son zamanlarda
sıklıkla tartışılan enerji krizi ve çevresel kirlilikten dolayı yeni ve daha
iyi termoelektrik malzemelerdeki araştırmalar hızla artmaktadır. Termoelektrik
malzemeler bu problemlerin çözümü için potansiyel yollardan biri olarak
görülmektedir. Yarı-Heusler malzemelerde büyük sıcaklık kararlılıklarından
dolayı termoelektrik malzemeler olarak düşünülmektedir. Tipik olarak
yarı-Heusler alaşımlar  uzay gruplu (No.216)
yüzey merkezli kübik yapıda kristallenir. Bu çalışmada ilkel hücresinde 8
elektrona sahip Li tabanlı LiTiAl bileşiğinin yapısal, elastik, elektronik ve
titreşimsel özellikleri ilk ilkesel yöntemler kullanan VASP paket programı
kullanılarak incelenmiştir. Hesaplamalarda 700 eV kesilim enerjisi ve 15x15x15
k-noktası kullanılmıştır. Örgü sabiti 6.191Å olarak hesaplanmıştır. Elde
edilen yapısal parametreler mevcut literatür sonuçları ile uyumludur.
Elektronik özellikler olarak band yapısı, toplam ve kısmi durum yoğunluğu
grafikleri çizilmiştir. Bu hesaplardan bu bileşiğin band aralığı 9.55 meV
olarak bulunmuştur. Elastik sabitleri zor-zorlanma oranından hesaplanmıştır.
Hesaplanan elastik sabitleri bu bileşiğin mekaniksel olarak kararlı olduğunu
göstermiştir. Fonon frekansları hesaplanmıştır ve yapı kararlı olarak
bulunmuştur. 

Keywords

LiTiAl, Yarı-Heusler, Titreşimsel özellikler, DFT, GGA-PBE

References

• [1]. Ouardi S., Fecher G.H., Felser C., Kübler J. 2013. Realization of Spin Gapless Semiconductors: The Heusler Compound Mn2CoAl. Phy. Rev. Lett. 110, 100401.
• [2]. Liu Z.H., Zhang M., Cui Y.T., Zhou Y.Q., Wang W.H., Wu G.H., Zhang X.X., Xiao G. 2003. Martensitic transformation and shape memory effect in ferromagnetic Heusler alloy Ni2FeGa. Appl. Phys. Lett. 82, 424.
• [3]. Klimczuk T., Wang C.H., Gofryk K., Ronning F., Winterlik J., Fecher G.H.,. Griveau J.C, Colineau E., Felser C., Thompson J.D., Safarik D.J., Cava R.J. 2012. Superconductivity in the Heusler Family of Intermetallics. Phys. Rev. B. 85, 174505.
• [4]. Bos J.-W.G., Downie R.A. 2014. Half-Heusler thermoelectrics: a complex class of materials. J. Phys. Condens. Matter 26, 433201. [5]. Duan C.G., Sabiryanov I.F., Mei W.N., Dowben P.A., Jaswal S. 2007. Electronic, magnetic and transport properties of rare-earth monopnictides. Journal of Physics: Condensed Matter. 19, 315220.
• [6]. Hu. X. 2012. Half-Metallic Antiferromagnet as a Prospective Material for Spintronics Adv. Mater. 24, 294-298.
• [7]. Mehnane H., Bekkouche B., Kacimi S., Hallouche A., Djermouni M. 2012. First-principles study of new half Heusler for optoelectronic applications. Superlattices and Microstructures 51, 772-784.
• [8]. Watanabe K. 1976. Magnetic Properties of Clb-Type Mn Base Compounds. Trans. Jpn. Inst. Met. 17, 220.
• [9]. de Groot R.A., Mueller F.M., van Engen P.G., Buschow K.H.J. 1983. New Class of Materials: Half-Metallic Ferromagnets. Phys. Rev. Lett. 50, 2024.
• [10]. Kacimi S., Mehnane H., Zaoui A. 2014. Kacimi S., Mehnane H., Zaoui A. 2014. I–II–V and I–III–IV half-Heusler compounds for optoelectronic applications: Comparative ab initio study. Journal of Alloys and Compounds 587, 451-458.
• [11]. Xie W., Weidenkaff A., Tang X., Zhang Q., Poon J. and Tritt T.M. 2012. Recent Advances in Nanostructured Thermoelectric Half-Heusler Compounds. Nanomaterials 2, 379-412.
• [12]. Kieven D. and Klenk R. 2010. I-II-V half-Heusler compounds for optoelectronics: Ab initio calculations. Phys. Rev. B 81, 075208.
• [13]. Xiao D., Yao Y., Feng W., Wen J., Zhu W., Chen X-Q., Stocks G.M., Zhang Z. 2010. Half-Heusler Compounds as a New Class of Three-Dimensional Topological Insulators Phys. Rev. Lett. 105, 096404.
• [14]. Casper F., Graf T., Chadov S., Balke B. and Felser C. 2012. Half-Heusler compounds: novel materials for energy and spintronic applications. Semicond. Sci. Technol. 27, 063001.
• [15]. Perdew J.P., Burke K. and. Ernzerhof M. 1996. Generalized Gradient Approximation Made Simple Phys. Rev. Lett. 77, 3865.
• [16]. Perdew J.P., Burke K. and Ernzerhof M. 1997. Generalized Gradient Approximation Made Simple Phys. Rev. Lett. 78, 1396.
• [17]. Kresse G. and Hafner J. 1993. Ab initio molecular dynamics for liquid metals. Phys. Rev. B. 47, 558.
• [18]. Kresse G. and Hafner J. 1994. Ab initio molecular-dynamics simulation of the liquid-metal–amorphous-semiconductor transition in germanium. Phys. Rev. B. 49, 14251.
• [19]. Kresse G.and Furthmüller J. 1996. Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set. Comput. Mat. Sci. 6, 15.
• [20]. Kresse G. and Furthmüller J. 1996. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B. 54, 11169.
• [21]. Chaput L., Togo A., Tanaka I. and Hug G. 2011. Phonon-phonon interactions in transition metals Phys. Rev. B. 84, 094302.
• [22]. Gruhn T. 2010. Comparative ab initio study of half-Heusler compounds for optoelectronic applications. Phys. Rev. B. 82, 125210.
• [23]. Engel E. and Vosko S.H. 1993. Exact exchange-only potentials and the virial relation as microscopic criteria for generalized gradient approximations. Phys. Rev. A. 47, 2800.
• [24]. Mehl J. 1993. Pressure dependence of the elastic moduli in aluminum-rich Al-Li compounds Phys. Rev. B. 47, 2493.
• [25]. Wang S.Q. and Ye H.Q. 2003. First-principles study on elastic properties and phase stability of III–V compounds. Phys. Status Solidi B. 240, 45.
• [26]. M. Born and K. Huang. 1956. Dynamical Theory of Crystal Lattices, Clarendon, Oxford.
• [27]. Pugh S.F. 1954. XCII. Relations between the elastic moduli and the plastic properties of polycrystalline pure metals. Phil. Mag. 45, 823.
• [28]. Bannikov V.V., Shein I.R. and Ivanovskii A.L. 2007. Electronic structure, chemical bonding and elastic properties of the first thorium-containing nitride perovskite TaThN3. Phys Status Solidi (RRL). 1, 89.
• [29]. Johnston, Keeler G., Rollins R., and Spicklemire S. 1996. Solid State Physics Simulations. The Consortium for Upper-Level Physics Software, John Wiley, New York.
• [30]. Togo A., Oba F. and Tanaka I. 2008. First-principles calculations of the ferroelastic transition between rutile-type and CaCl2-type SiO2 at high pressures. Phys. Rev. B. 78, 134106.
• [31]. Togo A. and Tanaka I. 2015. First principles phonon calculations in materials science. Scripta Materialia. 108, 1-5.
• [32]. H. Ozisik, K. Colakoglu, and Havva B. Ozisik. 2010. Ab-initio first principles calculations on half-Heusler NiYSn (Y=Zr, Hf ) compounds Part 1: Structural, lattice dynamical, and thermo dynamical properties. Fizika 16, 154.
• [33]. Shiomi J., Esfarjani K. and Chen G. 2011. Thermal conductivity of half-Heusler compounds from first-principles calculations. Phys. Rev. B 84, 104302.