ИСТИНА

In our work we present the investigation of La3CrGe3Be2O14, the new member of langasite family, combining 3d and 4f ions in the lattice. In this compound, Cr3+ (S = 3/2) ions occupy octahedral position 1a in the structure and organize one-dimensional magnetic chains along c direction with the distances ~ 5 Å between nearest Cr3+ ions in chain and ~ 8 Å between the chains. We investigated the magnetic susceptibility and specific heat of La3CrGe3Be2O14 in the range 1.8–320 K using Quantum Design PPMS. Temperature dependence of the magnetic susceptibility is shown in Fig. 1. It follows the Curie-Weiss law in the range 50–320 K. The value of the effective magnetic moment is 3.8mB for Cr3+. Antiferromagnetic Q_CW = –23 K allows to estimate roughly the magnetic exchange in 1D-chain as J ~ 5 K. The broad maximum at 16.5 K is a typical feature for the low-dimensional magnetism and the susceptibility behavior can be successfully modelled by the Fisher’s expression for Heisenberg S = 3/2 spin-chain with J = 7.6 K.