Proton NMDR of ethylene oxide dissolved in a nematic solvent

The generalized nuclear Overhauser effect evidenced by the INDOR technique has been used to analyze the PMR spectrum of ethylene oxide dissolved in a nematic phase solvent. This method allows the construction of the energy diagram of the spin system and an unambiguous determination of the sign of the direct coupling constants relative to the sign of the indirect coupling constants. Less common features such as double resonance on double quantum transitions and the repeated spacings effect were shown to be observable in nematic phases and to be useful in confirming the energy-level diagram.