Vibrational spectra of superdense lithium graphite intercalation compounds Original Research Article

IR investigations of lithium graphite intercalation compounds with different lithium in-plane density (LiC6, LiC4, LiC2) were carried out. The spectra interpretation was done on the basis of normal coordinate analysis for model structures. LiC2 and LiC4 spectra exhibit the bands corresponding to a complex skeleton stretching in Li7 or LiC6 clusters including equilateral triangles of metal atoms at short distances which shows that covalence exists between Li atoms in the intercalated layer and that LiC2 decomposition proceeds keeping these clusters in LiCx structure for x < 4 at least.