  Five compounds were investigated for magnetic character and
superconductivity, all with non-magnetic nickel and band structures containing
flat bands and steep bands. The syntheses and crystal structures, refined by
powder X-ray diffraction, are reported for M6Ni16Si7, where M = Mg, Sc, Ti, Nb,
and Ta. All compounds form in the Mg6Cu16Si7 structure type. Resistance
measurements are also reported on M6Ni16Si7 (M = Mg, Sc, Ti, and Nb) down to
0.3 K, with all four showing metallic conductivity. No superconductivity is
observed. Magnetization measurements for all compounds reveal essentially
temperature independent paramagnetism, with a tendency toward more enhanced low
temperature paramagnetism for the cases of Mg6Ni16Si7 and Sc6Ni16Si7.
