TY - JOUR
T1 - Physical properties of mononuclear organoeuropium sandwich complexes ligated by cyclooctatetraene and bis(trimethylsilyl)cyclooctatetraene
AU - Tsuji, Takashi
AU - Fukazawa, Suguru
AU - Sugiyama, Rion
AU - Kawasaki, Kenshiro
AU - Iwasa, Takeshi
AU - Tsunoyama, Hironori
AU - Tokitoh, Norihiro
AU - Nakajima, Atsushi
N1 - Funding Information:
Authors are grateful to Prof. S. Yabushita for his fruitful discussion and to Dr. Y. Mizuhata and Ms. T. Hirano for combustion analysis. This work is partly supported by MEXT-Supported Program for the Strategic Research Foundation at Private Universities, 2009–2013.
PY - 2014/3/18
Y1 - 2014/3/18
N2 - Mononuclear organoeuropium sandwich complexes were synthesized from ligands of 1,3,5,7-cyclooctatetraene (COT) and 1,4- and 1,6-bis(trimethylsilyl)- cyclooctatetraenes (COT″) in a liquid ammonia of europium (Eu) and lithium (Li). Elemental analyses revealed the chemical compositions as [(DME)Li] 2Eu(COT)2 (1) and [(DME)Li]2Eu(COT″) 2 (2). Vibrational analyses and magnetic measurements revealed a ligand-Eu-ligand sandwich structure. The Eu2+ ions induce paramagnetic behaviors at 6-300 K. Although UV-irradiated 1 and 2 emit light of similar color, the quantum yields of their toluene solution widely differ (2.4% and 21%, respectively). The effects of the trimethylsilyl group are evaluated from quantum chemical calculations.
AB - Mononuclear organoeuropium sandwich complexes were synthesized from ligands of 1,3,5,7-cyclooctatetraene (COT) and 1,4- and 1,6-bis(trimethylsilyl)- cyclooctatetraenes (COT″) in a liquid ammonia of europium (Eu) and lithium (Li). Elemental analyses revealed the chemical compositions as [(DME)Li] 2Eu(COT)2 (1) and [(DME)Li]2Eu(COT″) 2 (2). Vibrational analyses and magnetic measurements revealed a ligand-Eu-ligand sandwich structure. The Eu2+ ions induce paramagnetic behaviors at 6-300 K. Although UV-irradiated 1 and 2 emit light of similar color, the quantum yields of their toluene solution widely differ (2.4% and 21%, respectively). The effects of the trimethylsilyl group are evaluated from quantum chemical calculations.
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U2 - 10.1016/j.cplett.2014.01.034
DO - 10.1016/j.cplett.2014.01.034
M3 - Article
AN - SCOPUS:84894870157
SN - 0009-2614
VL - 595-596
SP - 144
EP - 150
JO - Chemical Physics Letters
JF - Chemical Physics Letters
ER -