Magnetic phase separation in [formula presented] by [formula presented] nuclear magnetic resonance

[Formula presented] NMR measurements on [Formula presented] reported here establish unequivocally, for the first time, the coexistence of ferromagnetic regions, spin-glass regions, and hole-poor low spin regions at all [Formula presented] values from 0.1 to 0.5. A zero external field NMR spectrum, which is assigned to the ferromagnetic regions, has a spectral shape that is nearly [Formula presented] independent at 1.9 K, as are the relaxation times, [Formula presented] and [Formula presented]. The integrated spectral area increases rapidly with [Formula presented] up to [Formula presented] and then decreases slightly for larger [Formula presented]. In a field of 9.97 T, a narrow NMR line is observed at 102 MHz, identical to that found in [Formula presented] samples in previous work. The integrated intensity of this spectrum decreases rapidly with increasing [Formula presented], and is ascribed to hole-poor low spin regions. Beneath this spectrum, a third broad line, with a peak at 100 MHz, is assigned to a spin- or cluster-glass-like phase.