ISOMER-MIXTURE METAL COMPLEX COMPOSITION, ORGANIC ELECTROLUMINESCENT ELEMENT, ILLUMINATOR, AND DISPLAY DEVICE

The present invention addresses the problem of providing an isomer-mixture metal complex composition that includes a plurality of atropisomers which are closely akin to each other in physical property and energy level and of providing an organic EL element using the isomer-mixture metal complex composition as a material for the organic EL element, the EL element having improved stability over time of the organometallic complex film, including a luminescent layer reduced in resistivity change, and giving a luminescent spectrum reduced in change in half-value width. Also provided are an illuminator and a display device which are obtained using the organic EL element. This isomer-mixture metal complex composition is a metal complex composition which is a mixture of isomers each comprising a metal atom and a plurality of ligands, and is characterized by containing a plurality of atropisomers because at least one of the ligands has an aromatic ring as a substituent and the free rotation of the axis of the bonding between the aromatic ring and the ligand is inhibited by the formation of a complex of the metal atom with other ligand(s).