Soluble Sm-based ternary complexes for non-contact molecular thermometry

We develop two soluble Sm-doped ternary complexes for use as two-color thermometry (TCT) phosphors. These complexes are Sm(acac)3(TOPO)2 and Sm(hfa)3(TOPO)2, which are doped into HTPB polymer and optically characterized as a function of temperature. Both materials are found to have similar TCT calibration curves with an average energy spacing of ΔE=99(±10)×10−3 eV and an intensity ratio proportionality constant of A=0.65±0.16. We estimate Sm(acac)3(TOPO)2's maximum functional temperature for continuous heating to be 497 K, while Sm(hfa)3(TOPO)2 is limited to 441 K due to irreversible thermal degradation of the complex. These complexes have promise as non-contact molecular temperature sensors in a wide variety of polymers and solvents.