The main photophysical properties, useful for establishing whether hypericin in anionic form and some of its derivatives containing heavy atoms such as iodine, can be proposed for their use in photodynamic therapy, were determined using density functional based computations. The results showed that in the anionic form and in the iodinated derivatives, the absorption wavelength undergoes a bathochromic shift, the singlet-triplet energy gap assumes values ​that allow to excite the oxygen molecule from its ground to the excited singlet state, and that the spin–orbit couplings between singlet and triplet states significantly increase.

中文翻译：

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金丝桃素及其含碘衍生物光动力活性的起源


使用基于密度泛函的计算确定了主要的光物理性质，可用于确定阴离子形式的金丝桃素及其某些含有重原子（如碘）的衍生物是否可用于光动力疗法。结果表明，在阴离子形式和碘化衍生物中，吸收波长发生红移，单重态-三重态能隙呈现允许将氧分子从基态激发到激发单重态的值，并且单线态和三线态之间的自旋轨道耦合显着增加。