ic402363s_si_001.cif (27.94 kB)
Download fileSynthesis, Crystal and Electronic Structure of the Quaternary Magnetic EuTAl4Si2 (T = Rh and Ir) Compounds
dataset
posted on 2014-02-03, 00:00 authored by Arvind Maurya, Arumugam Thamizhavel, Alessia Provino, Marcella Pani, Pietro Manfrinetti, Durga Paudyal, Sudesh Kumar DharSingle crystals of the quaternary
europium compounds EuRhAl4Si2 and EuIrAl4Si2 were synthesized by using the Al–Si
binary eutectic as a flux. The structure of the two quaternary compounds
has been refined by single crystal X-ray diffraction. Both compounds
are stoichiometric and adopt an ordered derivative of the ternary
KCu4S3 structure type (tetragonal tP8, P4/mmm). The two compounds reported
here represent the first example of a quaternary and truly stoichiometric
1:1:4:2 phase crystallizing with this structure type. In light of
our present results, the structure of the BaMg4Si3 compound given in literature as representing a new prototype is
actually isotypic with the KCu4S3 structure.
Local spin density approximation including the Hubbard U parameter (LSDA + U) calculations show that Eu
ions are in the divalent state, with a significant hybridization between
the Eu 5d, Rh (Ir) 4d (5d), Si 3p and Al 3p states. Magnetic susceptibility
measured along the [001] direction confirms the divalent
nature of the Eu ions in EuRhAl4Si2 and EuIrAl4Si2, which order magnetically near ∼11 and
∼15 K, respectively.