Crystal structure and properties of the titanium stannide Ti2Sn3

摘要

The recently reported binary stannide Ti2Sn3 is confirmed. Its structure was 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 factors 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 smaller coordination number. The two different titanium atoms of Ti2Sn3 have 11 neighbors of which 3 and 4, respectively, are titanium atoms. The three different tin atoms have 5 titanium with 8 or 10 additional tin neighbors. They show only a slightly broadened but unresolved Sn-119 Mossbauer signal with an isomer shift reflecting the high tin content of this intermetallic compound and a relatively large quadrupole splitting of 2.10 mm.s(-1). Ti2Sn3 is a good metallic conductor and a Pauli paramagnet. [References: 21]