Hydrogen Isotope Effects in Ti-V-Cr Alloy Hydrides

The hydrogen isotope effects are systematically investigated by measuring the equilibrium separation factor (alpha) in Ti-V-Cr alloys with mixed H-D systems at 30 degrees C. We find that all of the alloys are BCC structures except for TiCr. Interestingly, alpha displays a parabolic relation with respect to the number of valence electrons per metal atom (e/a) for V 40 at %. Moreover, significant inverse isotope effects appear at e/a = 4.6-5.2 (alpha > 1.3), and a reaches its maximum value at e/a = 5.0 (alpha = 1.47). The lattice constants dependent on a are studied by adjusting the vanadium content at e/a = 5.0, revealing a linear decrease of a as a function of the lattice constants. All the results indicate that the hydrogen isotope effects can be detected in Ti-V-Cr alloys with e/a and lattice constants.