Seven‐Coordinate Luminophores: Brilliant Luminescence of Lanthanide Complexes with C3v Geometrical Structures. Issue 28 (7th September 2015)

• Record Type: Journal Article
• Authors: Yanagisawa, Kei; Nakanishi, Takayuki; Kitagawa, Yuichi; Seki, Tomohiro; Akama, Tomoko; Kobayashi, Masato; Taketsugu, Tetsuya; Ito, Hajime; Fushimi, Koji; Hasegawa, Yasuchika
• Is Part Of: European journal of inorganic chemistry. Issue 28(2015)
• Page Start: 4769
• Page End: 4774
• Publication Date: 2015-09-07
• Subjects: Lanthanides -- Luminescence -- O ligands -- Structure elucidation -- Density functional calculations; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.201500820
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract: Enhanced luminescence properties of mononuclear lanthanide complexes with asymmetric seven‐coordination structures are reported for the first time. The lanthanide complexes are composed of a lanthanide ion (Eu III or Tb III ), three tetramethyl heptanedionato ligands, and one triphenylphosphine oxide ligand. The coordination geometries of the lanthanide complexes have been evaluated by using single‐crystal X‐ray analyses and shape‐measurement calculations. The complexes are categorized to be seven‐coordinate monocapped octahedral structures (point group C 3 v ). The seven‐coordinate lanthanide complexes show high intrinsic emission quantum yields, extra‐large radiative rate constants, and unexpected small nonradiative rate constants. The brilliant luminescence properties have been elucidated in terms of the asymmetric coordination geometry and small vibrational quanta related to thermal relaxation. Abstract : This work reports on lanthanide complexes with seven‐coordination structures that show brilliant luminescence properties owing to their asymmetric geometrical structure. The complexes exhibit extra‐large radiative rate constants and unexpected small nonradiative rate constants.