Patent ID: 8545807

Claim:
A near infrared high emission rare-earth complex, comprising three bidentate phosphine oxide ligands having a biphenyl base and three bidentate ligands which differ from the aforementioned ligands, wherein the complex has a structure expressed by a following general formula (1): where Ln is Yb; n is three; Xs represent either a same member or different members selected from a hydrogen atom, a deuterium atom, halogen atoms, C 1 -C 20 groups, hydroxyl groups, nitro groups, amino groups, sulfonyl groups, cyano groups, silyl groups, phosphonic groups, diazo groups and mercapto groups; and Z represents a bidentate ligand expressed by a general formula (2): where R 1 and R 2 are a same member or different members selected from C 1 -C 22 aliphatic groups free of hydrogen atoms, aromatic groups free of hydrogen atoms, and aromatic heterocyclic groups free of hydrogen atoms.