Structural and NMR study of the lithiated defect thiospinels LixCu0.07[Ti2]S4 (0 < x < 2)

Article abstract of DOI:10.1016/0022-4596(88)90259-9

Oxidative extraction of copper from the normal thiospinel Cu[Ti₂]S₄ followed by chemical lithiation of the resulting defect thiospinel enabled the metallic, lithiated defect thiospinels Li_xCu_0.07[Ti₂]S₄ to be prepared with high purity and chemical homogeneity. X-ray and neutron powder-diffraction studies of Li_xCu_0.07T[Ti₂]S₄ showed that lithium insertion into Cu_0.07[Ti₂]S₄ is topotactic and that the inserted lithium occupies only the 16c-octahedral sites of the thiospinel framework at all lithium compositions. Static and MAS ⁷Li NMR spectra of Li_xCu_0.07[Ti₂]S₄ exhibited a single lithium resonance with a small chemical shift relative to lithium acetate dihydrate at all lithium compositions; the chemical shift increased linearly with increasing lithium content.