A superconducting KBi
2 sample was successfully prepared using a liquid ammonia (NH
3) technique. The temperature dependence of the magnetic susceptibility (
M/
H) showed a superconducting transition temperature (
Tc) as high as 3.6 K. In addition, the shielding fraction at 2.0 K was evaluated to be 87%,
i.e., a bulk superconductor was realized using the above method. The
Tc value was the same as that reported for the KBi
2 sample prepared using a high-temperature annealing method. An X-ray diffraction pattern measured based on the synchrotron X-ray radiation was analyzed using the Rietveld method, with a lattice constant,
a, of 9.5010(1) Å under the space group of
Fdm (face-centered cubic, no. 227). The lattice constant and space group found for the KBi
2 sample using a liquid NH
3 technique were the same as those reported for KBi
2 through a high-temperature annealing method. Thus, the superconducting behavior and crystal structure of the KBi
2 sample obtained in this study are almost the same as those for the KBi
2 sample reported previously. Strictly speaking, the magnetic behavior of the superconductivity was different from that of a KBi
2 sample reported previously,
i.e., the KBi
2 sample prepared using a liquid NH
3 technique was a type-II like superconductor, contrary to that prepared using a high-temperature annealing method, the reason for which is fully discussed. These results indicate that the liquid NH
3 technique is effective and simple for the preparation of a superconducting KBi
2. In addition, the topological nature of the superconductivity for KBi
2 was not confirmed.A superconducting KBi
2 sample was successfully prepared using a liquid ammonia (NH
3) technique.
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