Abstract We have investigated the structural, electronic and magnetic properties of the equiatomic quaternary Heusler (EQH) alloys FeCrRuZ (Z = Al, Ga, In, Si) using density functional theory. The structural study reveals that all the FeCrRuZ (Z = Al, Ga, In, Si) alloys stabilized to Y1 type structural configuration with ferrimagnetic ordering. The spin-polarized density of states (DOS) calculation demonstrates that FeCrRuAl alloy exhibits unusual spin-gapless half-metallic (SG-HM) behavior with majority spin-up channel possessing metallic characteristic and minority spin-down channel showing spin-gapless nature. The FeCrRuSi, FeCrRuGa and FeCrRuIn alloys display half-metallic, nearly half-metallic and metallic nature, respectively. The FeCrRuAl and FeCrRuSi alloys greatly follow the Slater-Pauling rule and give 100% spin-polarization at the Fermi level with total integer magnetic moment of 1 and 2 μB, respectively. In all, the total magnetic moment of FeCrRuZ (Z = Al, Ga, In, Si) alloys is contributed mainly by Cr atoms. The origin of the half-metallic band gap is elucidated through a schematic molecular orbital (MO) diagram. Further, the role of main group elements on structural, electronic, magnetic and half-metallic properties are explored in greater detail.

中文翻译：

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基于 3d-4d 过渡金属的 LiMgPdSn 型 FeCrRuZ（Z = Al、Ga、In、Si）等原子四元赫斯勒合金的第一性原理计算

摘要 我们使用密度泛函理论研究了等原子四元赫斯勒 (EQH) 合金 FeCrRuZ (Z = Al、Ga、In、Si) 的结构、电子和磁性能。结构研究表明，所有 FeCrRuZ（Z = Al、Ga、In、Si）合金均稳定为具有亚铁磁性有序的 Y1 型结构配置。自旋极化态密度 (DOS) 计算表明，FeCrRuAl 合金表现出不寻常的自旋无间隙半金属 (SG-HM) 行为，其中大多数自旋向上通道具有金属特性，少数自旋向下通道具有自旋无隙性质。FeCrRuSi、FeCrRuGa 和 FeCrRuIn 合金分别显示出半金属、近半金属和金属性质。FeCrRuAl 和 FeCrRuSi 合金极大地遵循 Slater-Pauling 规则，在费米能级上产生 100% 自旋极化，总磁矩分别为 1 和 2 μB。总之，FeCrRuZ（Z = Al、Ga、In、Si）合金的总磁矩主要由Cr原子贡献。通过分子轨道（MO）示意图阐明了半金属带隙的起源。此外，更详细地探讨了主族元素对结构、电子、磁性和半金属特性的作用。