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The compounds KZnTiF6, KZnVF6, KVScF6, KCrScF6, and KMnScF6 are fluoride analogs of Tetragonal Tungsten Bronze. M2+–M3+ ionic ordering in these fluorides provided systems which contained linear trinuclear complexes of their respective paramagnetic ions. Magnetic coupling within these linear trimers occurred below 100 K in each of the five systems. Derived magnetic susceptibility equations were fitted to observed magnetic susceptibilities for each of the possible spin systems: KZnTiF6 (S=1/2), J/k=−114 K; KZnVF6 (S=1), J/k=−39 K; KVScF6 (S=3/2), J/k=−16 K; KCrScF6 (S=2), J/k=−4 K; and KMnScF6 (S=5/2), J/k=−7.5 K.

A{sub x}VF{sub 3} (A=K, Rb, Cs; x=0-1.0) and A{sub x}CrF{sub 3} compounds were sealed inside high-temperature DTA molybdenum sample cups using electron beam welding techniques. Melting temperatures of the A{sub x}VF{sub 3} compounds ranged from 1050 to 1400 deg. C; those of A{sub x}CrF{sub 3} from 850 to 1200 deg. C. Reconstructive transitions were observed for A{sub x}VF{sub 3} compounds between 650 and 950 deg. C, and for A{sub x}CrF{sub 3} compounds between 550 and 825 deg. C. A displacive transition was observed to occur in VF{sub 3} at 490 deg. C. Order-disorder transitions were determined by X-ray diffraction techniques. In the A{sub x}VF{sub 3} compounds, electronic ordering and ordering of partially filled A{sup +} sites were observed to occur between 100 and 300 deg. C. Ordering phenomena in the A{sub x}CrF{sub 3} compounds (in addition to electronic ordering and ordering of partially filled A{sup +} sites) included Jahn-Teller cooperative ordering. These compounded transitions occurred between 300 and 500 deg. C.