화학공학소재연구정보센터
Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, Vol.285, 573-578, 1996
Photoluminescence of Enantio-Selectively Formed Chromium(III) Double Salts
Chromium complex double salts of the compositions [Cr(en)(3)] [Cr(ox)(3)] and [Cr(pn)(3)][Cr(ox)(3)] (en=ethylenediamine, pn=propylenediamine, ox-oxalate), denoted as [en][ox] and [pn][ox], respectively, were prepared from racemic and optically resolved component complexes. (+) or (-) [Cr(en)(3)](3+) selectively combines with homochiral [Cr(ox)(3)](3-) to form a chiral double salt, which has a different structure and a different low-temperature photoluminescence spectrum with respect to the racemic [en][ox] compound. The luminescence at 15 K is due to the (2)E(g) --> (4)A(2g) transition of the oxalate complex. The total luminescence spectrum and the circularly polarized luminescence (CPL) spectrum of chiral [en][ox] are dominated by a progression in a 213 cm(-1) mode with S = 0.31. Racemic [pn][ox] also shows a luminescence spectrum with a pronounced vibronic progression.