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Ag3LiIr2O6 is a Kitaev spin liquid candidate material synthesised from α-Li2IrO3 through a topotactic reaction. We investigate the structural and magnetic properties of two samples of Ag3LiIr2O6 based on 7 Li nuclear magnetic resonance line shape, Knight shift and spin-lattice relaxation rate 1/T1. The first sample A shows signatures of magnetically ordered spins, and exhibits one sharp 7 Li peak with FWHM increasing significantly below 14 K. 1/T1 of this sample displays a broad local maximum at 40 K, followed by a very sharp divergent behaviour at TN = 9 ± 1 K when bulk magnetic long range order sets in. In order to investigate the influence of structural disorder, we compare these NMR results for a second sample B, which has been shown by transmission electron microscope to have unwanted Ag inclusion at Li and Ir sites within the Ir honeycomb planes. The sample B displays an additional NMR peak with relative intensity of ∼ 17%. The small Knight shift and 1/T1 of these defect-induced 7 Li sites suggest that Ir spins in their vicinity become only weakly magnetic at low temperatures, leading to an apparent spin liquid like behaviour. We use numerical Inverse Laplace Transform T1 (ILTT1) analysis based on Tikhonov regularization to determine the distribution of 1/T1 and compare the results between the two samples.

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