  The Ce(1-x)LaxCrGe3 (x = 0, 0.19, 0.43, 0.58 and 1) intermetallic compound
system has been investigated by magnetization measurements and neutron
scattering techniques to determine the effect of La-doping on the magnetic
ordering and exchange interaction between Cr ions. The structural and magnetic
characterization in this series was first verified by X-ray diffraction and
bulk magnetization measurements. The samples exhibit the known hexagonal
perovskite structure (P63/mmc space group) and have a single magnetic phase
according to magnetization measurements. In this work, the ferromagnetic
ordering temperature for Cr evolves smoothly from a range of 68 K to 77 K for
CeCrGe3 to a range of 91 K to 96 K for LaCrGe3 as La replaces Ce. Magnetization
results indicate the formation of domain walls below the transition temperature
for all the Ce(1-x)LaxCrGe3 systems investigated. Neutron results indicate
ordered magnetic Cr moments aligned along the c axis for the x = 1 LaCrGe3
system, as well as for x = 0.19, 0.43, and 0.58, which contrasts with the x = 0
CeCrGe3 where the moments order in the ab plane.
