Domain microstructure related to lattice distortion in La1-x Pbx MnO3

In this letter we report a transmission electron microscopy investigation of the occurrence of different orientation states in La1-x Pbx MnO3 and demonstrate its correlation with the rhombohedral distortion of this compound. We show that the observed twinned microstructure is consistent with that expected from groupsubgroup relations between the prototype and the room-temperature phase. Domain wall orientations are derived from ferroelastic theory. The relation between the observed distortion and structural parameters is discussed.