Observation of superconductivity in the organometallic intercalation compound SnSe2{Co(η-C5H5)2}0.33

Intercalation of phosphorus-doped SnSe2 with bis(cyclopentadienyl) cobalt {Co(η5-C5H5)2} produces superconducting SnSe2{Co(η5-C5H5)2}0.33 with a critical temperature of 6 K; magnetisation measurements show a hysteresis loop with a maximum at 40 G, indicating type II superconducting behaviour; the lower critical field (Bc1) is estimated at 10 G at 4.2 K and the critical current density (Ic) is ca. 500 A cm–2 at 2.5 K; the diamagnetic susceptibility corresponds to 13% of perfect diamagnetism.