Features of the photochromic behavior of spiroanthrooxazine in solutions

Spirooxazines: synthesis, structure, spectral and photochromic properties

“…However, since the photochromic fragments in these compounds are not independent, their simultaneous photoexcitation presents problems. Of three biphotochromic compounds of the type B considered below, viz., SPO ± SPO 188, 134,135 As a result, the absorption spectra of the coloured forms of these compounds are shifted to the IR region.…”