Spectral and Photochromic Properties

The data currently available on the rates and quantum efficiency of the photocoloration reactions la — lb of perimidinespirocyclohexadienones and their analogs are rather scarce. The values of the quantum yield for the photoconversion of compound la under excitation at its long-wavelength absorption band were determined with the use of the Aberchrome 540 actinometer. These are given in Table 8.3. 

Relative rates of photocoloration ( colorabilities 24) have been determined as slopes of the D(t) - / absorbance curve obtained by measurement of the rate of 

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The methods of synthesis, the spectral and photochromic properties in solution, in polymer film and in vacuum-deposited thin films, and the structural determinations by X-ray diffraction are reviewed as is the electrochemical behavior of this family of switchable materials. 

Synthesis, structure, spectral, and photochromic properties of spirooxiranes 02UK1015. 

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