Abstracts

Due to its electronic structure, which presents thermally coupled levels, and their absorption/emission bands that lies in the biological windows, neodymium(III) cation possesses advantages to be used in luminescent thermometry for bio-applications. This cation has been used in several materials, such as nanoparticles, glasses or MOFs, proving its optimal characteristics.In the present work, a novel family of neodymium(III) based molecular compounds will be presented, covering from synthesis, characterization up to luminescent thermometry in the NIR region. Macrocyclic motifs were used, together with different anions that were selected to impart different coordination geometries. The analysis is focused to the molecular point of view, by analysing the coordination environments of the cation in the different species and its influence in the spectroscopies properties. The thermometric properties were studied exciting in the first biological window and analysing emission in the second biological window, analysing its temperature dependence in the physiological temperature range. The most intense band was c.a. 1065nm, which presents different splitting in agreement with the present of other coordination environments. By deconvolution it was possible to identified each components, in order to analyse its temperature dependency. The spectroscopic characteristic and the present of different component in each sample was confirmed by theoretical calculations. Among all samples, an hexanuclear complex highlights due to the higher sensibility of Sr of 3.7 %K-1 at 293 K, and more important because luminescence intensity ratio of two components of the 1065 nm transition was achieved.