Nonpolarized light absorption in pure, doped with the nitrite ions, and photolyzed KNO3 crystals

Absorption of nonpolarized light by pure, doped with the nitrite ions, and photolyzed KNO3 crystals has been studied. It is shown that the absorbance registered in nonpolarized light, directed perpendicular to the crystallographic c axis of both pure doped with the nitrite ions crystals, linearly depends on the thickness of crystal in the region of high (A > 0.5) and low (A < 0.3) absorbance. With the photolysis time increase one can observe the shift of maximum absorption band due to peroxynitrite formed under photolysis of KNO3 crystal. The shape of peroxynitrite absorption band calculated as the difference between a total spectrum and host matrix spectrum depends on the absorbance in the maximum of the former.