Influence of metal ions on the structure and spectral properties of TCNQ salts with tris(phenanthroline) cations

• Crystal structure of TCNQ salts containing [M(phen)3]2+ cations (M is Mn, Fe or Co).
• IR and Raman spectra of [M(phen)3](TCNQ)2 anion-radical salts.
• DFT calculations of the o-phenantroline derived cations.

New anion-radical TCNQ salts containing o-phenanthroline complex cations with metal ions and appropriate solvent molecules were structurally and spectrally investigated. Contrary to the majority of TCNQ salts the structure of the investigated salts do not contains anion-radical stacks. It was stated that anisotropy of Raman spectra is negligent whereas the form of IR absorption spectra suggests very weak electron–molecular vibrations couplings. On the other hand the IR spectra of the cations are dominated mainly by the vibrations of the phenanthroline ligands. The Raman spectra of the investigated salts are differentiated and are altogether unlike each other. Some bands of complex cations located between 1100 and 1650 cm−1 show particular character and can characterize metal–phenantroline cation.