fig4

Figure 4. (A) ²⁷Al MAS NMR spectrum of the same Al-LLZO sample; (B) An enlargement of the same spectrum to show the resonances corresponding to Al in tetrahedral environments; (C) DQ-SQ 2D spectrum for the same Al-LLZO sample. Copyright 2023, American Chemical Society^[67]; (D) ⁶Li MAS NMR spectra of Li_7-2x-3yAl_yLa₃Zr_2-xW_xO₁₂ (0 ≤ x ≤ 1). Copyright 2015, American Chemical Society^[68]. MAS: Magic angle spinning; NMR: nuclear magnetic resonance; LLZO: Li₇La₃Zr₂O₁₂; DQ: Double quantum; SQ: single quantum.