Fluorinated graphite oxides (FGO) and fluorinated lignin (FL) have been investigated by X-ray photoelectron spectroscopy (XPS). In the F1s spectra of both compounds a peak with the energy being intermediate between the value in a typical ionic compound LiF and covalent compounds of type (CF)(n) and-(CF2-CF2)(n)- was extracted. The substances under study, even at high oxidizer content, contain structure fragments with carbon having sp(2)-bybridized orbitals. The bond formed between fluorine and these fragments is of semi-ionic type. The temperature, which allows the semi-ionic fluorine-carbon bond formation, is found to be between the room temperature and 100 degrees C. The registration of semi-ionic state of fluorine in the n allows to assume that the layered structure of initial substance is not necessary for the formation of semi-ionic bond between fluorine and carbon.