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A single crystal of the indium-rich intermetallic compound EuPtIn4 has
been grown by a high-temperature solution growth method, with molten
indium as solvent. The crystal structure of the compound was solved from
the single crystal X-ray diffraction data and it is found that EuPtIn4
crystallizes in the orthorhombic crystal structure with the space group
Cmcm. The estimated lattice constants are a = 4.5300(7) angstrom, b =
16.904(3) angstrom, and c = 7.3601(12) angstrom with the unit cell
volume V = 563.60(15) angstrom(3). There are four formula units per unit
cell (Z = 4), and the R-parameters are R = 0.0390 and wR(2) = 0.1033 for
496 unique reflections. A comparison of lattice constants with those of
isostructural SrPtIn4, LaPtIn4, EuPtIn4, and eYbPtIn(4) indicates that
the radius of the rare-earth ion decides the indium octahedra distortion
in the bc-plane. This leads to nonmonotonic variation in b and c
parameters from the early to the late rare earth element based
compounds. EuPtIn4 is a highly conducting material, with a room
temperature resistivity of 25 mu Omega.cm. Low-temperature resistivity,
magnetization, and heat capacity measurements show two antiferromagnetic
transitions near 13 and 5.5 K. From the heat capacity data it was
observed that EuPtIn4 has a large Sommerfeld coefficient (gamma), which
was estimated to be 725 mJ/K-2.mol.
