Raman and infrared spectra of graphite-AlCl3

Raman and infrared spectra on well-staged graphite-Al${\mathrm{Cl}}_3$ are reported for compounds with stages $n=1, 2, 4, \mathrm{and} 8$. Of significance is the absence of infrared-active modes for stage-1 graphite-Al${\mathrm{Cl}}_3$ and the presence in stages 2, 4, and 8 of three infrared-active modes in the vicinity of the graphite $E_{1u}$ mode. The Raman-active modes in graphite-Al${\mathrm{Cl}}_3$ behave similarly to the corresponding bounding-layer and interiorlayer graphitic modes in graphite-Fe${\mathrm{Cl}}_3$ with regard to the stage dependence of the peak frequencies and relative intensities.