a b s t r a c tFirst-principle calculations were performed to investigate the structural, electronic and magnetic properties of Zn x Mn 1Àx O compounds (x ¼ 0.0, 0.25, 0.50, 0.75 and 1.0) in a wurtzite-type structure. The full-potential linearized augmented-plane-wave (FP-LAPW) method was used, as implemented in the WIEN2k code. The analysis of the structural properties shows that the constant increases linearly according to Vegard's law, with the increment of the Zn concentration in the structure, while the bulk modulus increases. The electronic density studies show that the Zn x Mn 1Àx O compounds (x ¼ 0.25, 0.50 and 0.75) have a half-metallic behavior with a magnetic spin polarization of 100% and a magnetic moment of~5 m b /atom-Mn. The ferromagnetic state comes from the hybridization of the Mn-3d and O2p states that cross the Fermi level. These compounds are good candidates for spintronic applications.

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principles calculations 20Magnetic ordering 21 2 2 a b s t r a c t 23 We employed density functional theory (DFT) in order to study the structural, electronic, and magnetic 24 properties of pure AlN and C-atom-doped AlN compounds. The calculations were carried out using the 25 method based on pseudopotential, employed exactly as implemented in Quantum ESPRESSO code. For 26 the description of the electron-electron interaction, generalized gradient approximation (GGA) was used. 27 The calculations showed that the substitution of a C atom at the N site introduces a magnetic moment of 28 about 1.0 l B , while two C atom substitutions introduce a magnetic moment of about 2.0 l B . These mag-29 netic properties become hybridization states C-2p and their first neighboring Al-2p and first neighboring 30 N-2p atoms. Calculated magnetic properties indicate that C-doped AlN compound can potentially be used 31 in diluted magnetic semiconductors.32 Ó 2015 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http:// 33 creativecommons.org/licenses/by-nc-nd/4.0/). 34 35 36 Introduction 37 AlN stabilizes in the wurtzite structure in bulk form [1]. AlN, as 38 the largest band-gap semiconductor material, has many superior 39 properties, and thus is the best material for constructing devices 40 in the violet region. It is also used as electronic packaging material 41 and is applied to optical disks as well as lithographic photo masks 42 [2-4]. Aluminum nitride exhibited stability at high temperatures, 43 considerable thermal conductivity, low thermal expansion, and 44 high resistance to gases and chemicals [5]. Recently, AlN has 45 received extensive attention because of its possible use as a diluted 46 magnetic semiconductor (DMS) with potential application in the 47 field of spintronics. For these applications, ferromagnetism at room 48 temperature is a requirement. In recent years, high-temperature 49 ferromagnetism has been reported by many researchers in several 50 types of transition-metal (TM)-doped semiconducting oxides and 51 nitrides [6-8]. However, it was found that the magnetic TM 52 dopants in TM-doped DMS segregate to form ferromagnetic clus-53 ters, precipitate, or secondary phases [9-11]. This represents a 54 big obstacle for practical applications of diluted magnetic semicon-55 ductors. To avoid this problem, many researchers have focused on 56 investigating the effect of nonmagnetic ion doping in semiconduc-57 tors in order to obtain high-temperature ferromagnetic 58 semiconductors. Experimental results have proved that it is 59 possible to obtain high-temperature ferromagnetism in nonmag-60 netic anion, for example nonmagnetic C-and N-doped ZnO, TiO 2 61 and C-doped GaN [12-14]. In this paper, we present first-62 principles total energy calculations of the structural, electronic, 63 and magnetic properties of AlC 0.0625 N 0.9375 and AlC 0.125 N 0.875 com-64 pounds. First we calculated the structural parameters of pure AlN 65 and the two ternary compounds considered in this s...

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