Palladium enables optical activity and surface plasmon effects in the ultraviolet (UV). However, low UV matrix transmittance has largely prevented any exploitation of Pd optical centers embedded in glasses. Here, we report on speciation of palladium dopants in various types of UV‐transparent glasses, including fluoride‐phosphate, sulfo‐phosphate and meta‐phosphate. We initially employ quantum chemical simulation and physical experimentation on aqueous solutions in order to generate reference data for Pd²⁺ band assignments in different ligand arrangements. These data are then used to assign the extinction spectra of Pd‐doped glasses. Square‐planar is identified as the most probable configuration of Pd²⁺ complexes in all studied materials, with a pronounced preference for sulfate ligands in the sulfo‐phosphates. Annealing at moderate temperature can be employed for the thermal reduction of Pd²⁺ and precipitation of metallic particles. However, the plasmon frequency of Pd particles with a diameter of less than 50 nm strongly overlaps with the Pd²⁺ charge transfer bands.

中文翻译：

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紫外线透明玻璃中的钯形态

钯在紫外线（UV）中具有光学活性和表面等离激元效应。但是，低的紫外线基体透射率很大程度上阻止了对嵌入玻璃中的Pd光学中心的任何利用。在这里，我们报告了各种类型的紫外线透明玻璃中钯掺杂剂的形态，包括氟化物磷酸盐，磺基磷酸盐和偏磷酸盐。我们最初在水溶液中采用量子化学模拟和物理实验，以便为不同配体排列中的Pd ²⁺谱带分配生成参考数据。这些数据然后用于指定掺Pd的玻璃的消光光谱。方平面被认为是Pd ²⁺最可能的配置在所有研究的材料中都具有复杂的配合物，其中磺基磷酸盐中的硫酸盐配体具有明显的优势。在中等温度下的退火可用于Pd ²⁺的热还原和金属颗粒的沉淀。但是，直径小于50 nm的Pd粒子的等离激元频率与Pd ²⁺电荷转移带强烈重叠。