Abstract K2SO4:Cu2+ (3%) crystal has been synthesized and its crystal structure is characterized by means of the X-ray diffraction method and discussed within the second coordination environment description. Experimental dispersions of the refractive indices and birefringence have been studied. The introduction of impurity leads to a decrease in refractive indices values for all principal directions and significantly change the absolute birefringence values, without altering the character of the dispersions. Electronic structure and optical spectra of K2SO4:Cu2+ (3%) crystal are calculated using the density functional theory. To verify data of the present band-structure calculations, X-ray photoelectron spectroscopy and X-ray emission spectroscopy were used. These allowed to measure binding energy values of the core-level electrons of the constituting atoms, energy distribution of electronic states within the valence-band region and partial distribution of O 2p states. The experimental data is found to be in good agreement with theoretical band-structure calculations.

中文翻译：

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K2SO4:Cu2+ (3%) 晶体的结构、折射和电子特性

摘要 合成了 K2SO4:Cu2+ (3%) 晶体，并通过 X 射线衍射法表征了其晶体结构，并在第二配位环境描述中进行了讨论。已经研究了折射率和双折射的实验色散。杂质的引入导致所有主要方向的折射率值降低，并显着改变绝对双折射值，而不会改变色散的特性。使用密度泛函理论计算 K2SO4:Cu2+ (3%) 晶体的电子结构和光谱。为了验证当前能带结构计算的数据，使用了 X 射线光电子能谱和 X 射线发射光谱。这些允许测量构成原子的核心能级电子的结合能值、价带区内电子态的能量分布和 O 2p 态的部分分布。发现实验数据与理论能带结构计算非常吻合。