Novel ternary compound Ce4Pt9Al13: Crystal structure, physical properties

The crystal structure of the novel Al-rich intermetallic phase Ce ₄Pt ₉Al ₁₃ was determined from single-crystal X-ray diffraction data and confirmed by powder X-ray diffraction. The compound crystallizes with its own structure type, which is a “site exchange” variant of the Ho ₄Ir ₁₃Ge ₉-type (Pearson symbol oP52, space group Pmmn, No. 59, Z = 2, lattice parameters: a = 4.1826(1) Å b = 11.4424(3) Å c = 19.8475(5) Å V = 949.88(7) Å ³). The magnetic properties of Ce ₄Pt ₉Al ₁₃ were determined in the temperature range 1.72–400 K. Down to the lowest temperatures studied, the compound shows a Curie-Weiss paramagnetic behavior with strong crystalline electric field contribution observed below about 200 K. The electrical conductivity in Ce ₄Pt ₉Al ₁₃ has metallic character, and at low temperatures it is governed by an interplay of strong crystal field and Kondo interactions.