Raman spectra of neutron-irradiated pyrolytic graphite

Raman spectra of pyrolytic graphite after neutron irradiation at 50 K and annealing up to room temperature have been studied by a laser Raman spectrometer. In addition to the ominpresent line at 1580 cm-1, a Raman line has been observed at 1623 cm-1 which can be ascribed to C2 molecules. Another line has also been observed at 1361 cm-1, already reported in ground graphite, carbon blacks and activated carbons. This line is discussed in relation to point defects produced by neutron irradiation. (author)