Theoretical Investigation On 7-azaindole Derivatives

Since Tang and VanSlyke reported the first double-layer green organicelectroluminescent(EL) device using Alq3(q=8-hydroxyquinolinyl) in 1987, therehave been intense research activities in organic EL devices. Blue emitters for organicdevices remain the most soughtafter materials.In order to get the stableluminescent/eluctroluminescent compounds ,Qingguo Wu synthesized a series of7-azaindole compounds .But unexpectedly some of new compounds of 7-azaindolederivatives had been found to be promising in EL devices. We studied thederivatives: 1,3-Di(N-7-azaindolyl)benzene,1,3,5-Tri(N-7-azaindolyl)benzene and4,4′Di(N-azaindoly)biphenyl from theory calculation and found why they hadluminescence properties and if solvent such as CH2Cl2 had any effect on theirluminescence.Calculations on the electronic ground state of the three compounds wer carriedout using B3LYP density function theory.The excited-state geometries wer optomozedat the CIS level,CIS/6-31g(d).The transition energies will calculated at both theground-state and excited-state geometries by ZINDO and TD-DFT/B3LYPcalculations,and results are compared with the available experimental data.The natureof theexcited states,as well as the positive and negative ions with regard to"electron-hole"creation ,is relevance to their using in OLED materials.All thecalculations are performed with Gaussian03 software package i\using a spin-restrictedformalism at B3LYP/6-31g(d) level of theory.From the calculations,we found that 1,3-Di(N-7-azaindolyl)benzene1,3,5-Tri(N-7-azaindolyl)benzene and 4,4′Di(N-azaindoly)biphenyl shared almost...