The vibrational and electronic spectra of the mono‐, di‐, and trianon salts of TCNQ

摘要: The vibrational and electronic spectra for the sodium mono‐, di‐, trianion salts of TCNQ prepared in vacuo by solvent‐free vapor codeposition methods, have been measured. These data, combined with published assignments neutral monoanion TCNQ, permitted an empirical analysis effect increasing charge on π‐ bonding this conjugated system. Thus, molecular force constants determined from new assignments, which are somewhat tentative case di‐ trianion, indicate a regular transition p‐quinoid ring system TCNQ0 to benzenoid TCNQ3−. Simultaneously, C≡N C≡C bonds wings considerably reduced strength while wing C––C gain double bond character eventually surpassing original C=C dianion salt, Na2TCNQ, is colorless Na3TCNQ, golden yellow but there little evidence eit...