| abstract |
The present invention aims to provide organic EL elements etc., containing phosphorescent organometallic complexes, that can exhibit longer durability, higher emitting efficiency, superior thermal/electrical stability, significantly longer operating life. The organic EL elements comprise an organic thin layer interposed between a positive hole transport layer and a electron transport layer, the organic thin layer comprises an organometallic complex comprising at least a metal element, a tridentate ligand, and a monodentate ligand, wherein the tridentate ligand bonds with the metal atom through two nitrogen atoms and one carbon atom, and the carbon atom exists between the two nitrogen atoms, and a monodentate ligand bonds with the metal atom through a atom selected from the group consisting of C, N, O, P and S atoms. |