An investigation of La1-xSrxMnO3 near x=0.5

We have done a systematic study of the ac susceptibility, dc magnetization, and ferromagnetic resonance in a set of polycrystalline samples of La1-xSr xMnO3 with nominal x values varying from 0.46 to 0.53 at 0.01 intervals. Ap art from noting the remarkable changes attendant on small variations in x, it is found that at low T, one has coexistence of ferromagnetic and antifer romagnetic phases. The resonance data are interpreted to provide a measure for the size of the ferromagnetic regions. (C) 2000 American Institute of P hysics. [S0021-8979(00)26308-1].