TY - JOUR
T1 - Shining light on the excited state energy cascade in kinetically inert Ln(iii) complexes of a coumarin-appended DO3A ligand
AU - Junker, Anne Kathrine R.
AU - Sorensen, Thomas Just
PY - 2019
Y1 - 2019
N2 - Our understanding of the solution structure of the complexes between a coumarin-appended 1,4,7,10-tetraazacyclododecane-1,4,7-triacetate (DO3A) ligand and Eu(iii), Gd(iii), Tb(iii) and Y(iii) ions allows us to investigate the excited state energy transfer cascade that result in sensitised lanthanide centred luminescence, and we can do so in unprecedented detail. Spectroscopic data from solutions with ambient oxygen levels, without oxygen and solid solutions at 77 K unequivocally show that the simple model for the antenna principle is not valid. We find that the Tb(iii) complex photophysics is determined by the non-emissive 5 D 3 state, not the emissive 5 D 4 state as usually assumed. This scrutiny of the energy transfer cascade in these antenna appended lanthanide complexes, show that detailed knowledge of solution structure and experimental photophysics are needed to rationalise the properties of lanthanide based dyes.
AB - Our understanding of the solution structure of the complexes between a coumarin-appended 1,4,7,10-tetraazacyclododecane-1,4,7-triacetate (DO3A) ligand and Eu(iii), Gd(iii), Tb(iii) and Y(iii) ions allows us to investigate the excited state energy transfer cascade that result in sensitised lanthanide centred luminescence, and we can do so in unprecedented detail. Spectroscopic data from solutions with ambient oxygen levels, without oxygen and solid solutions at 77 K unequivocally show that the simple model for the antenna principle is not valid. We find that the Tb(iii) complex photophysics is determined by the non-emissive 5 D 3 state, not the emissive 5 D 4 state as usually assumed. This scrutiny of the energy transfer cascade in these antenna appended lanthanide complexes, show that detailed knowledge of solution structure and experimental photophysics are needed to rationalise the properties of lanthanide based dyes.
U2 - 10.1039/c8dt04464c
DO - 10.1039/c8dt04464c
M3 - Journal article
C2 - 30566150
SN - 1477-9226
VL - 48
SP - 964
EP - 970
JO - Dalton Transactions (Print Edition)
JF - Dalton Transactions (Print Edition)
IS - 3
ER -