Crystal structure and properties of the titanium stannide Ti2Sn3

The recently reported binary stannide Ti2Sn3 is confirmed. Its structure wa s determined From single-crystal X-ray diffractometer data: Cmca, a = 596.7 (4), b = 1995(2), c = 701.3(4) pm, Z = 8, R = 0.027 for 817 structure facto rs and 30 variable parameters. The crystal structure is compared to that of V2GaSn2, which has the same space group symmetry and atomic positions. The Ga atoms of V2GaSn2 occupy those Sn positions of Ti2Sn3 which have the sma ller coordination number. The two different titanium atoms of Ti2Sn3 have 1 1 neighbors of which 3 and 4, respectively, are titanium atoms. The three d ifferent tin atoms have 5 titanium with 8 or 10 additional tin neighbors. T hey show only a slightly broadened but unresolved Sn-119 Mossbauer signal w ith an isomer shift reflecting the high tin content of this intermetallic c ompound and a relatively large quadrupole splitting of 2.10 mm.s(-1). Ti2Sn 3 is a good metallic conductor and a Pauli paramagnet.