Neutron diffraction study on heavy-fermion compound CeCrGe3

We present a comprehensive powder neutron diffraction study on the heavy-fermion Kondo lattice system CeCrGe3 which orders ferromagnetically below T-C = 70 K. The neutron diffraction data corroborate the presence of magnetic Bragg peaks below T-C which could be indexed with the propagation vector (k) over right arrow = (0 0 0). Due to the presence of a very few magnetic reflections at low T, we have used ratio of intensities between the temperatures below (10 K) and above T-C (80 K) to analyze magnetic structure, rather than the conventional Rietveld refinement method. Our analysis of the magnetic structure reveals an ordered magnetic moment of 1.1(1) mu B for the Cr moments and 0.8(2) mu B for the Ce moments where both are aligned in the ab plane at T = 10 K. Remarkably, the presence of Ce moment is found to have a strong correlation with Cr moment and sets the Cr moments to order in the ab plane rather than along the c axis which was seen in 4f(0) counterpart, i.e., LaCrGe3.