부산대학교 도서관

Four novel organic–inorganic hybrid nicotinate-bridging dimeric rare-earth (RE)-containing phosphotungstates [H 2 N(CH 3 ) 2 ] 8 [RE(H 2 O)(NA)( α -HPW 11 O 39 )] 2 ·24H 2 O (RE = Ho III for 1 , Er III for 2, Tb III for 3 , Dy III for 4 ; HNA = nicotinic acid) have been synthesized from the reaction of trivacant Keggin precursor Na 9 [ α -PW 9 O 34 ]∙16H 2 O, RE(NO 3 ) 3 ·6H 2 O, HNA by employing dimethylamine hydrochloride as organic solubilizing agent in the conventional aqueous solution system, which have been further characterized by elemental analyses, IR spectra, thermogravimetric analyses and single-crystal X-ray diffraction. Structural analysis indicates that the hybrid dimeric {[RE(H 2 O)(NA)( α -HPW 11 O 39 )] 2 } 8− polyoxoanion in 1 – 4 can be considered as two head-to-head mono-RE-containing Keggin [RE(H 2 O)(NA)( α -HPW 11 O 39 )] 4− subunits bridged by two ( η 2 , μ -1,1)-nicotinate linkers, which stands for the first organic–inorganic hybrid RE-containing phosphotungstates functionalized by nicotinate ligands. What's more, the solid-state photoluminescence properties and lifetime decay behaviors of 1 – 4 have been measured at room temperature and their photoluminescence spectra display the characteristic emission bands of corresponding trivalent RE cations. [ABSTRACT FROM AUTHOR]