STEADY-STATE SPECTRAL CHARACTERISTICS OF 1-PHENYL-3-PYRAZOLIDINONE INDIFFERENT ENVIRONMENTS

Analysis of steady state absorption spectra of 1-phenyl-3-pyrazolidino ne (PPd) in different organic solvents at ambient temperature shows th at it is strongly polarity dependent which is associated with intramol ecular charge transfer. A correlation is shown between the appearance of dual fluorescence of PPd in alcoholic solutions at 300 K and the fo rmation of hydrogen bonded solute-solvent complexes. Evolution of a ne w band at the red end of the absorption spectra of PPd in all the solv ents with traces of water impurities and the fluorescence study in aqu eous beta-cyclodextrin solutions establish beyond doubt that a PPd mol ecule has a high affinity to water molecules. Phosphorescence spectra are also recorded in methyl cyclohexane and ethanol matrices at 77 K.