Section of Chemistry and Chemical Engineering, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
Institut des Sciences et Ingénierie Chimique, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
Molecules. 2020 Sep 3;25(17):4022. doi: 10.3390/molecules25174022.
Europium, terbium, dysprosium, and samarium are the main trivalent lanthanide ions emitting in the visible spectrum. In this work, the potential of these ions for colorimetric applications and colour reproduction was studied. The conversion of spectral data to colour coordinates was undertaken for three sets of Ln complexes composed of different ligands. We showed that Eu is the most sensitive of the visible Ln ions, regarding ligand-induced colour shifts, due to its hypersensitive transition. Further investigation on the spectral bandwidth of the emission detector, on the wavelengths' accuracy, on the instrumental correction function, and on the use of incorrect intensity units confirm that the instrumental correction function is the most important spectrophotometric parameter to take into account in order to produce accurate colour values. Finally, we established and discussed the entire colour range (gamut) that can be generated by combining a red-emitting Eu complex with a green-emitting Tb complex and a blue fluorescent compound. The importance of choosing a proper white point is demonstrated. The potential of using different sets of complexes with different spectral fingerprints in order to obtain metameric colours suitable for anti-counterfeiting is also highlighted. This work answers many questions that could arise during a colorimetric analysis of luminescent probes.
铕、铽、镝和钐是发射可见光光谱的主要三价镧系离子。在这项工作中，研究了这些离子在比色应用和颜色再现方面的潜力。对于由不同配体组成的三组 Ln 配合物，将光谱数据转换为颜色坐标。我们表明，Eu 是最敏感的可见 Ln 离子，由于其超敏感跃迁，配体诱导的颜色位移。进一步研究发射探测器的光谱带宽、波长精度、仪器校正函数以及使用不正确的强度单位，证实仪器校正函数是为了产生准确的颜色值而必须考虑的最重要的分光光度参数。最后，我们建立并讨论了可以通过组合发射红色的 Eu 配合物、发射绿色的 Tb 配合物和蓝色荧光化合物来产生的整个颜色范围（色域）。证明了选择适当的白点的重要性。还强调了使用具有不同光谱指纹的不同配合物组来获得适合防伪的同色异谱颜色的潜力。这项工作回答了在发光探针的比色分析中可能出现的许多问题。
