Influence of Halogen Atoms on a Homologous Series of Bis-Cyclometalated Iridium(III) Complexes
作者:Etienne Baranoff、Basile F. E. Curchod、Filippo Monti、Frédéric Steimer、Gianluca Accorsi、Ivano Tavernelli、Ursula Rothlisberger、Rosario Scopelliti、Michael Grätzel、Md. Khaja Nazeeruddin
DOI:10.1021/ic2011474
日期:2012.1.16
iridium(III) complexes Ir(2,4-di-X-phenyl-pyridine)2(picolinate) (X = H, F, Cl, Br) HIrPic, FIrPic, ClIrPic, and BrIrPic has been synthesized and characterized by NMR, X-ray crystallography, UV–vis absorption and emission spectroscopy, and electrochemical methods. The addition of halogen substituents results in the emission being localized on the main cyclometalated ligand. In addition, halogen substitution
一系列同源的双环金属化铱(III)配合物Ir(2,4-di-X-苯基-吡啶)2(吡啶甲酸)(X = H,F,Cl,Br)HIrPic,FIrPic,ClIrPic和BrIrPic已通过NMR,X射线晶体学,UV-vis吸收和发射光谱以及电化学方法进行了合成和表征。卤素取代基的添加导致发射定位在主要的环金属化配体上。另外,卤素取代引起发射最大值的蓝移,特别是在基于氟的类似物的情况下,但是对于氯和溴取代基不太明显。在基态和激发态理论计算的支持下,我们通过考虑最高占据分子轨道(HOMO)和最低未占据分子轨道(LUMO)能级上的σp和σmHammett常数,以简单的方式合理化了这种影响。此外,与FIrPic和ClIrPic相比,大溴原子的影响显着降低了BrIrPic的光致发光量子产率,并将相应的寿命从单指数衰减转换为双指数衰减。我们基于线性响应时间相关的密度泛函理论(LR-TDDFT)进行了理论计