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The results of x-ray fluorescence measurements of the molecular superconductors ͑ET͒ 4 ͓͑H 3 O͒Fe͑C 2 O 4 ͒ 3 ͔•C 6 H 5 CN (T c ϭ8.5 K) and ͑ET͒ 4 ͓͑H 3 O͒Cr͑C 2 O 4 ͒ 3 ͔•C 6 H 5 CN (T c ϳ6 K) and molecular conductor ͑ET͒ 4 ͓͑H 3 O͒Fe͑C 2 O 4 ͒ 3 ͔•C 5 H 5 N containing paramagnetic 3d ions are presented. The following transition of the x-ray emission valence spectra are monitored: C K␣, N K␣ (2p→1s transition͒ and Fe L 2,3 , Cr L 2,3 (3d4s→2p 3/2,1/2 transition͒. It is found that the electronic structure of the solvents ͑benzonitrile, pyridine͒ that occupy the hexagonal cavities formed by the anionic layer is close to that of the neutral molecule. The ratio of the emission intensities of the peaks L 2 to L 3 for Fe and Cr is found to be 2.8-3.1 times higher for ͑ET͒ 4 ͓͑H 3 O͒Fe͑C 2 O 4 ͒ 3 ͔•C 6 H 5 CN and ͑ET͒ 4 ͓͑H 3 O͒Cr͑C 2 O 4 ͒ 3 ͔•C 6 H 5 CN than for pure metals. This indicates that the paramagnetic 3d ions are situated in highly insulating anionic layers. We did not find any changes in the C K␣ emission for different solvent molecules.The charge transfer salts based on the donor ET molecule ͓bis ͑ethylenedithio͒ tetrathiafulvalene͔ cover a wide range of electrical conductivity from highly conducting metallic and superconducting to wide band gap semiconducting and insulating.