We present optical absorption spectra from the ultraviolet to the visible for size selected neutral Ag_n clusters (n = 5–120) embedded in solid Ne. We compare the spectra to time-dependent density functional calculations (TDDFT) that address the influence of the Ne matrix. With increasing size, several highly correlated electron excitations gradually develop into a single surface plasmon. Its energy is situated between 3.9 and 4.1 eV and varies with size according to the spherical electronic shell model. The plasmon energy is highest for clusters with atom numbers fully filling states with the lowest radial quantum number (e.g. 1s, 1p, 1d,...). TDDFT calculations for clusters with several candidate geometrical structures embedded in Ne show excellent agreement with the experimental data, demonstrating that the absorption bands depend only weakly on the exact structure of the cluster.

中文翻译：

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选定大小的中性Ag团簇的光学性质：电子壳结构和表面等离子体共振†

我们为嵌入固体Ne中的选定大小的中性Ag _n团簇（n = 5–120）提供了从紫外到可见光的吸收光谱。我们将光谱与解决Ne矩阵影响的随时间变化的密度泛函计算（TDDFT）进行了比较。随着尺寸的增加，几个高度相关的电子激发逐渐发展为单个表面等离子体激元。它的能量在3.9和4.1 eV之间，并且根据球形电子外壳模型的大小而变化。对于原子序数完全填充且原子序数最小的状态的簇，其等离激元能量最高（例如，1s，1p，1d ...）。对嵌入了几种候选几何结构的Ne团簇的TDDFT计算与实验数据显示出极好的一致性，这表明吸收带仅弱地依赖于团簇的确切结构。