A hint of superconducting transition has been observed for the first time i
n a cation radical salt derived from bisethyl-enethio-tetrathiafulvalene (B
ET-TTF), the salt (BET-TTF)(2)Br . 3H(2)O. Here the synthesis, X-ray struct
ure, and physical properties of two hydrated halides of BET-TTF that are is
ostructural and present stable metallic properties are described. The Figur
e is a perspective view of the crystal structure of (BET-TTF)(2)Br .3H2O, l
ayers of BET-TTF radical cation alternating along the a-direction with poly
meric anion networks.