Raman spectroscopic studies were carried out in the oxygen-isotope exchanged (La1-xNdx)(0.7)Ca0.3MnO3. We found that the phonon frequency and width are different for the ferromagnetic (FM) metallic and charge-order (CO) phases due to a difference in the local structure of each phase. Our data provide evidence for the coexistence of the FM and CO phases below about 100 K in the O-16 sample and below 50 K in the O-18 sample of (La0.5Nd0.5)(0.7)Ca0.3MnO3. (C) 2002 Elsevier Science B.V. All rights reserved.