Historically, ~7Li NMR started in 1946 with Li~+ aqueous solutions whereas Li-alkyl where first studied in the early sixties. In spite of the importance of lithiated organic compounds in organic synthesis and its high sensitivity , 7Li has not contributed so much to the development of NMR, like ~1H, ~(13)C, ~(17)O and ~(15)N because its predicted chemical shift range (5ppm) is the smallest of the periodic table. The shift from Phenyl-CH_2Li to Butyl-Li is only 2 ppm and solvent dependant. NMR of this alkaline chemistry has been reviewed. Only research in Li-metal and alloys used the larger specific shift produced by the Pauli paramagnetism, called Knight shift and summarised with a very clear NMR abstract for experimentalists. At that time, 1975, solid state Li-graphite studies were just beginning with first systematic synthesis of graphite-Li compounds. During the year 76, we obtained first ~7Li NMR spectra of LiC_6 compound. These first studies revealed immediately that Li-graphite compounds, having large paramagnetic shifts, temperature independent, are true alloys, with a completely new intercalation bonding, the lithium atom being above and under the centers of two superposed C-hexagons. This is completely different from the C-Li bond, where Li-atom is fixed only to one carbon, like H in C-H, and which ~7Li NMR line remains within a few ppm shift / Li~+ in LiCl. It was also shown, from line width studies, that a fast atomic Li motion was present at room temperature. In this lecture, we first present the specificities of Li nuclei and NMR. Then we describe briefly various defined Li-graphite compounds and the NMR results. Chapter three would describe the results of calculations obtained on the structure of this new Li-C bond, which explain most of NMR results. After that, experimental results obtained with other kinds of solid carbons like disordered ones, used for carbon anodes, fullerenes and nanotubes would be described and commented. This text has been edited in 2000 by T ANSO (191, pp. 62-70). It is more complete than my lecture 3 from the Li NMR viewpoint.
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