Planar Nets of Ti Atoms Comprising Squares and Rhombs in the New Binary Antimonide Ti₂Sb

Abstract

The new binary antimonide Ti(2)Sb was found to crystallize in a distorted variant of the La(2)Sb type, which contains a square planar La net with short La-La bonds. In the Ti(2)Sb structure, the corresponding Ti net is deformed to squares and rhombs in order to enhance Ti-Ti bonding, as proven by single-crystal X-ray investigation in combination with the real-space pair distribution function technique utilizing both X-ray and neutron powder diffraction data. Electronic structure calculations revealed a lowering of the total energy caused by the disorder, the major driving force being strengthened Ti-Ti interactions along the diagonal of the Ti(4) rhombs.

Hydrogen in Ti3Sb and Ti2Sb: Neutron vibrational spectroscopy and neutron diffraction studies

“…Therefore, in order to understand the structural basis of the fast localized H jump motion in Ti 3 SbH x [16], we have performed a new investigation of the positions of hydrogen atoms in the Ti 3 Sb hydride complemented by the study of the vibrational spectra of H(D) atoms in this system. The structure of the tetragonal Ti 2 Sb phase appearing as an impurity in our Ti 3 Sb sample was reported only a few years ago [17]. The hydriding properties of this new phase have not been studied so far.…”

Square net distortion engineering in the ternary variants of titanium antimonide, Ti2−δMδSb (M=Zr, Hf)

“…The amplitude of the distortion is smaller than in Ti 2 Sb, with the separation of the split site position being 0.39 Å rather than 0.52 Å [6], implying that introduction of heavier Zr atoms to the system decreases the distortion.…”

“…The patterns obtained after arc-melting showed strong resemblance to that of Ti 2 Sb [6], although with increasing d all peaks in the powder pattern shifted toward lower 2q Bragg angles. This implies that the larger M atoms were incorporated in the structure and thereby enlarged the unit cell.…”

“…2b. The I4/mmm model with distortions in the Ti2 net was referred to as a split site model in the previous paper on Ti 2 Sb [6].…”

“…During our further investigations of the M 2 Q compounds [1e5], where M is an early transition metal and Q is a pnictogen or chalcogen atom, we recently uncovered the new binary titanium antimonide, Ti 2 Sb [6]. Our initial structure analyses suggested the La 2 Sb structure type [7] for Ti 2 Sb.…”