A Tale of Two Polymorphs - Growth and Characterization of alpha-LnNiGa(4) (Ln = Y, Gd-Yb) and beta-LnNi(1-x)Ga(4) (Ln = Tb-Er)

作者：Menard Melissa C; Drake Brenton L; McCandless Gregory T; Thomas Kandace R; Hembree Richard D; Haldolaarachchige Neel; DiTusa John F; Young David P; Chan Julia Y

来源：European Journal of Inorganic Chemistry, 2011, 2011(26): 3909-3919.

DOI：10.1002/ejic.201100289

• Crystal growth
• Magnetic properties
• Intermetallic phases
• Gallium

The single crystals of two polymorphs of LnNiGa(4), namely, the orthorhombic alpha-LnNiGa(4) (Ln = Y, Gd-Yb) and, a new polymorph, the tetragonal beta-LnNi(1-x)Ga(4) (Ln = Tb-Er), were successfully grown by using the self-flux method. alpha-LnNiGa(4) (Ln = Y, Gd-Yb) is isostructural to YNiAl4 and can be described as an edge-sharing polyhedral of Ni@Ga(7)Ln(2) (Ln = Y, Gd-Yb) along the ac-plane that is sandwiched between the square nets of the Ga atoms along the b-axis. The structure of beta-LnNi(1-x)Ga(4) (Ln = Tb-Er) is a distorted variant of the Ce2NiGa10-structure type with a Ni deficiency and multiple Ga split positions and is structurally related to YNiGa3Ge. The magnetic data for beta-LnNi(1-x)Ga(4) (Ln = Tb-Er) and the transport properties for alpha-LnNiGa(4) (Ln = Y, Gd-Tm) and beta-LnNi(1-x)Ga(4) (Ln = Tb-Er) are reported. Antiferromagnetic correlations are observed in the magnetic susceptibility of beta-LnNi(1-x)Ga(4) (Ln = Tb-Er), where the magnetic transitions occurred below 7 K and with effective moments that are consistent with free Ln(3+) ions.

• 出版日期2011-9