La-139 NMR investigation of quasistatic orbital ordering in La1-xCaxMnO3 -art. no. 177204

We report La-139 nuclear magnetic resonance in ferromagnetic and insulating (FMI) La1-xCaxMnO3, 0.10 less than or equal to x less than or equal to 0.2 0, which at low temperatures shows the formation of Mn octants with enhance d Mn-O wave function overlapping and electron-spin alignment. The rapid inc rease of the relaxation rates and the "wipeout" of the La-139 NMR signal in tensity on heating, imply a quasistatic character for the Mn octant cells i n the FMI phase, which freeze below a transition temperature T-f.