Silver coloured, brittle single crystals of the metallic conducting compoun
d Na2AuSn3 were synthesized by reaction of sodium azide with gold sponge an
d tin powder at T = 820 K. The structure of the new compound (space group P
6(3)/mmc, Z = 4, a = 9.585(1) Angstrom, c = 7.516(2) Angstrom) was determin
ed from X-ray single-crystal diffractometry data. Na2AuSn3 crystallizes in
a ternary variant (Lu2CoGa3 type) of the AlB2 type. The tin atoms form the
motif of a (1)(infinity)[Sn-3/3] tubular fragment of the hexagonal diamond
structure. The (1)(infinity)[Sn-3/3] tubes are connected to a framework str
ucture via gold atoms with a trigonal planar tin coordination. The sodium a
toms are placed in channel-like cavities of the Au-Sn partial structure.