Observation of alkaline earth complexes M(CO)8 (M = Ca, Sr, or Ba) that mimic transition metals

  title={Observation of alkaline earth complexes M(CO)8 (M = Ca, Sr, or Ba) that mimic transition metals},
  author={Xuan Wu and Lili Zhao and Jiaye Jin and Sudip Pan and Wei Li and Xiaoyang Jin and Guanjun Wang and Mingfei Zhou and Gernot Frenking},
  pages={912 - 916}
Carbonyls in the s block Conventional wisdom in chemistry distinguishes transition metals from other elements by their use of d orbitals in bonding. Wu et al. now report that alkaline earth metals can slide their electrons from s- to d-orbital bonding motifs as well (see the Perspective by Armentrout). Calcium, strontium, and barium all form coordination complexes with a cubic arrangement of eight carbonyl ligands and an 18-electron valence shell. The compounds were characterized in frozen neon… 
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