| abstract |
Provided is a material for organic electroluminescence device containing (a) a phosphorescent metal complex containing a monoanionic bidentate ligand and a metal having an atomic weight of 40 or greater, wherein the monoanionic bidentate ligand is represented by the following formula (A): n n n n n n n n n n n n wherein, each of E 1a , E 1d , E 1e , E 1f , E 1k , E 1l , E 1p , and E 1q independently represents a carbon atom or a hetero atom, each of Z 1 , Z 2 , and Z 3 independently represents an aromatic ring or aromatic heterocycle, the aromatic ring or aromatic heterocycle may have a substituent, and a skeleton represented by the formula (A) has, in total, a 18π electron structure, and the bidentate ligand represented by the formula (A) may be coupled to another ligand to form a tridentate or higher-dentate ligand; and (b) a structural isomer represented by the same chemical formula as that of the phosphorescent metal complex (a) but different sterically in a coordination method of the ligand, wherein the structural isomer (b) is contained in an amount of 0.05 mass % or greater but not greater than 5 mass % relative to the phosphorescent metal complex (a). |