An Anomalous Electron Configuration Among 3 d Transition Metal Atoms

• Published in: Angewandte Chemie International Edition 2023-02, Vol.62 (7)
• Main Authors: Tang, Zhexin, Shang, Tongtong, Xu, Han, Lin, Ting, Gao, Ang, Lin, Weiguang, Li, Xinyan, Wang, Shiyu, Yu, Botao, Meng, Fanqi, Zhang, Qinghua, Wang, Xuefeng, Su, Dong, Meng, Qingbo, Wu, Lijun, Gu, Lin, Nan, Ce‐Wen
• Format: Article
• Language: English
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202216898

Physical properties of materials are mainly determined by valence electron configurations, where different valence shells would induce divergent phenomena. In compounds containing Sc 2+ , 3 d electron occupancy is expected, the same as other transition metal atoms like Ti 3+ . But this situation still awaits experimental verification in inorganic materials. Here, we selected ScS to measure the valence electron density and orbital population of Sc 2+ through delicate quantitative convergent‐beam electron diffraction. With the absence of 3 d orbital features around Sc‐atom sites and the nearly bare population of t 2g orbital, the unintuitive occupation of 4 s orbital in Sc 2+ is concluded. It should be the first time to report such a special electron configuration in a transition metal compound, in which 4 s rather than 3 d orbital is preferred. Our findings reveal the distinct behavior of Sc and probable ways to modulate material properties by controlling electron orbitals.