A nuclear magnetic resonance study of85Rb,87Rb, and19F in paramagnetic RbMnF3is reported. The measured shifts of the rubidium nuclear resonances are the first reported for the case of an alkali nucleus in the paramagnetic XMF3perovskite compounds (X = Na, K, Rb, Cs; M = Mn, Ni, Co). The shift for rubidium is in the opposite direction from that expected from a 5scontact hyperfine interaction. The isotropic hyperfine interaction of the fluorine indicates the presence of 0.51 unpaired 2sspins in the Fmdash;orbitals from each Mn+ +neighbor; this result is in good agreement with previous work for the Fmdash;resonances in these paramagnetic materials. The anisotropic shift of the Fmdash;resonance was examined in a powder sample and a 2phyperfine coupling coefficient obtained.
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