Circularly polarized emission studies on Tb3+ and Eu3+ complexes with potentially terdentate amino acids in aqueous solution.
Circularly polarized emission (CPE) and total emission (TE) spectra are reported for Eu3+ and Tb3+ complexes of L-aspartic acid (L-asp), L-serine (L-ser), L-threonine (L-thr) and L-histidine (L-his) in D2O solution under various pH conditions. Variations in TE and CPE intensities and in CPE splittings and sign patterns as functions of solution pH are correlated with lanthanide ion/ligand binding characteristics and with structural changes in the coordination environment of the metal ion. In the Eu3+/amino acid systems, the emission bands associated with the 5D0 leads to 7F1 and 7F2 Eu3+ transitions are monitored, and in the Tb3+/amino acid systems the 5D4 leads to 7F5 Tb3+ emission is examined.
D000596:Amino Acids; D001224:Aspartic Acid; D001665:Binding Sites; D002942:Circular Dichroism; D005063:Europium; D006639:Histidine; D006863:Hydrogen-Ion Concentration; D012694:Serine; D013725:Terbium; D013912:Threonine
D000596:Amino Acids; D013725:Terbium; D013912:Threonine; D001224:Aspartic Acid; D005063:Europium; D012694:Serine; D006639:Histidine