Calculation of the Vibrational Spectra of Linear Tetrapyrroles. 2. Resonance Raman Spectra of Hexamethylpyrromethene Monomers
作者:Maria-Andrea Mroginski、Károly Németh、Ildikó Magdó、Martin Müller、Uwe Robben、Carlos Della Védova、Peter Hildebrandt、Franz Mark
DOI:10.1021/jp000444h
日期:2000.11.1
The resonance Raman (RR) spectra of monomeric 3,3‘,4,4‘,5,5‘-hexamethylpyrromethene (HMPM) were measured upon excitation in resonance with the strong 436 nm absorption band. The experimental spectra were analyzed by comparison with calculated RR spectra that were obtained on the basis of scaled quantum chemical force fields in combination with the transform theory. The ground-state structure and force
单体 3,3',4,4',5,5'-六甲基吡咯亚甲基 (HMPM) 的共振拉曼 (RR) 光谱在 436 nm 强吸收带的共振激发下进行测量。通过与基于比例量子化学力场结合变换理论获得的计算RR光谱进行比较来分析实验光谱。HMPM 的基态结构和力场通过密度泛函理论 (DFT) 使用 B3LYP 交换泛函和 6-31G* 基组进行计算。与 HMPM 二聚体相比,单体 HMPM 采用平面结构,其中分子间氢键相互作用引起次甲基桥的轻微扭转,如实验和计算结构所示。通过使用先前确定的一组全局缩放因子来缩放力场(Magdo, I.;Nemeth, K.;Mark, F.;Hildebrandt, P.;Schaffner, KJ Phys. Chem. A 1999, 103, 289) . 为了解释分子内水合物的影响...