Crystal structure analysis of the Ti3ZrFe2O0.3D6.4 and TiZr3Fe2O0.3D7.5 deuterides

 

Chem. Met. Alloys 7 (2014) 100-105

 

I.Yu. ZAVALIY, R.V. DENYS, A.. RIABOV, I.V. KOVALCHUCK, P.Ya. LYUTYY

 

The crystal structures of two saturated deuterides, Ti3ZrFe2O0.3D6.4 and TiZr3Fe2O0.3D7.5, have been investigated by both X-ray and neutron powder diffraction. Hydrogenation of these oxygen-stabilized η-phases with Ti2Ni-type structure proceeds through expansion of their unit cells by 15.5 and 17.3 %, respectively, without change of the type of metal matrix. In both cases deuterium atoms fill tetrahedral interstices D2 (192i) and D3 (96g) with (Ti,Zr)3Fe surrounding, and T2 (32e) triangular interstices with (Ti,Zr)3 surrounding. In the case of Ti3ZrFe2O0.3 the octahedral interstice D7 (8a) with (Ti,Zr)6 surrounding is filled as well, whereas in the case of TiZr3Fe2O0.3 the triangular interstice T1 (32e) with (Ti,Zr)3 surrounding is filled as well. The insertion of deuterium atoms into the metal matrix of η-TiZr3Fe2O0.3 induces partial transfer of oxygen atoms from 1 (16c) octahedra into D7 (8a) octahedra.

 

 

Types of interstice (D1-D8 and O) in the (Ti,Zr)4Fe2Ox structure.

 

Keywords

Titanium and zirconium alloys / Metal hydrides / Crystal structure / X-ray diffraction / Powder neutron diffraction