Dipartimento di Chimica and Centro di Calcolo ad Alte Prestazioni per Elaborazioni Parallele e Distribuite-Centro di Eccellenza MIUR, Università della Calabria, I-87030 Arcavacata di Rende, Italy.
J Comput Chem. 2012 Apr 30;33(11):1091-100. doi: 10.1002/jcc.22914. Epub 2012 Feb 28.
The conformational structure and electronic spectra properties of a series of bay substituted perylenediimides (PDI) derivatives have been investigated by means of density functional theory (DFT) and time-dependent DFT. The B3LYP and PBE0 hybrid exchange-correlation functionals were applied in conjunction with the double-ζ quality SVP basis set. These compounds are interesting for organic materials science and as photosensitizers in cancer phototherapy (PDT), because of their intense absorption in the visible region. Results show that the substitution at the bay position of the PDI parent molecule with N-alkyl groups shifts the absorption maxima towards the red part of the visible spectrum (around 650-700 nm) as required for the applications in PDT. The main PDT action mechanisms have been investigated by computing of electron affinities, ionization potentials, triplet energies and spin-orbit matrix elements between singlet and triplet excited states.
通过密度泛函理论（DFT）和含时密度泛函理论（TD-DFT）研究了一系列取代苝二酰亚胺（PDI）衍生物的构象结构和电子光谱性质。采用 B3LYP 和 PBE0 杂化交换相关泛函，并结合双 ζ 质量 SVP 基组。这些化合物因其在可见光区的强吸收而在有机材料科学和癌症光疗（PDT）中的光敏剂方面具有重要意义。结果表明，PDI 母体分子在并位上用 N-烷基取代后，吸收最大值向可见光谱的红光部分（约 650-700nm）移动，这是 PDT 应用所需要的。通过计算电子亲和能、电离势、三重态能量和单重态和三重态激发态之间的自旋轨道矩阵元，研究了主要的 PDT 作用机制。
