Electride

Cavities and channels in an electride

An electride is an ionic compound in which an electron serves the role of the anion.[1] Solutions of alkali metals in ammonia are electride salts.[2] In the case of sodium, these blue solutions consist of [Na(NH3)6]+ and solvated electrons:

Na + 6 NH3 → [Na(NH3)6]+ + e−

The cation [Na(NH3)6]+ is an octahedral coordination complex. Despite the name, the electron does not leave the sodium-ammonia complex, but it is transferred from Na to the vacant orbitals of the coordinated ammonia molecules.[3]

  1. ^ Dye, J. L. (2003). "Electrons as Anions". Science. 301 (5633): 607–608. doi:10.1126/science.1088103. PMID 12893933. S2CID 93768664.
  2. ^ Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. ISBN 0-12-352651-5
  3. ^ Zurek, Eva; Edwards, Peter P.; Hoffmann, Roald (2009-10-19). "A Molecular Perspective on Lithium–Ammonia Solutions". Angewandte Chemie International Edition. 48 (44): 8198–8232. doi:10.1002/anie.200900373. ISSN 1433-7851.