The hydrogen-bonded supramolecular complexes（Fn and 2F6） were prepared by the complexation of carboxylic acid derivatives and 4,4′-bipyridine.The IR spectroscopic study on Fn and 2F6 shows that they were formed through single hydrogen bonding between —COOH and pyridyl groups.Fn showed a nematic state,while no liquid crystalline behaviour was observed for 2F6.
The effects of pressure on the fluorescence emission and Raman spectra of 1,4-bis[（4-methyloxyphenyl）-1,3,4-oxadiazolyl]- 2,5-bisheptyloxyphenylene （OXD-2） and on the fluorescence emission spectra of 1,4-bis[（4-methylphenyl）- 1,3,4-oxadiazolyl]phenylene （OXD-1） are investigated using a diamond anvil cell. With the increase of pressure, the intensity of the fluorescence emission increases and reaches maxima at 13GPa for OXD-1 and at 9.6GPa for OXD-2. The effect of pressure on the peak position of the emission shows a similar trend, red shift with the increase of pressure. But at higher pressures, the intensity of emission drops down dramatically. The Raman spectra of OXD-2 indicate that there appears a structural change at ca 3GPa.
