Dc-magnetization, x-ray diffraction, and Raman-scattering studies in polycrystalline (La12yNdy)12xCaxMnO3 (y50.0,0.5,1.0, andx51/3) samples are presented. The samples with y50.5 and 1.0 show complex magnetic states at low temperatures, with a ferromagnetic coupling strength that weakens with increasingy. X-ray measurements show a single crystallographic phase at all temperatures for y50.5, with lattice parameter anomalies at temperatures related to electronic and magnetic transitions. The presence of high-frequency vibrational modes in Raman-scattering measurements indicates the existence of chargeand orbital-ordered domains for y50.5 and 1.0, which are closely related to the antiferromagnetic component identified by the magnetization experiments. The close relationship between results obtained by magnetic, structural, and optical probes is discussed.