Synthesis and crystal structure of the new indide La8Co2In3

• The new ternary indide La8Co2In3 has been synthesized.
• The crystal structure has been determined by X-ray single crystal method.
• This compound crystallizes in new structure type (space group Pbam).
• Indium substructure represents the RuB2 structure type.

A new ternary indide La8Co2In3 was prepared by arc-melting of the compact metals under an argon atmosphere. A subsequent high temperature treatment was used for single crystal growth. The crystal structure has been determined from X-ray single crystal data: own structure type, space group Pmn21, Pearson code oP26, Z = 2, a = 10.2646(11), b = 10.1802(12), c = 7.3235(8) Å, R1 = 0.0338, wR2 = 0.0458, for 1556 independent reflections with I > 2σ(I) and 71 variables. Similarly to intermetallic compound with a high rare earth content, atoms in the title structure have no high coordination numbers: 12–15 for lanthanum, 9 and 7 for cobalt, and 11 for indium. Strong Co–Co bonding is observed in the structure. The packing of In polyhedra can be represented as a complicated variant of the RuB2 structure type.

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