| Abstract
| - X-ray data on single crystals of the quaternary metal hydride nearthe composition LiB0.33N0.67H2.67, previously identified as “Li3BN2H8”,reveal that its true composition is Li4BN3H10. The structure hasbody-centered-cubic symmetry [space group I213, cell parametera = 10.679(1)−10.672(1) Å] and contains an ordered arrangementof BH4- and NH2- anions in the molar ratio 1:3. The borohydrideanion has an almost ideal tetrahedral geometry (∠H−B−H ∼ 108−114°), while the amide anion has a nearly tetrahedral bond angle(∠H−N−H ∼ 106°). Three symmetry-independent Li atom sitesare surrounded by BH4- and NH2- anions in various distortedtetrahedral configurations, one by two B and two N atoms, anotherby four N atoms, and the third by one B and three N atoms. TheLi configuration around B is nearly tetrahedral, while that aroundN resembles a distorted saddlelike configuration, similar to thosein LiBH4 and LiNH2, respectively.
- A quaternary metal hydride, previously identified as “Li3BN2H8”, has the true composition Li4BN3H10. The cubic structure contains an ordered arrangement of BH4- and NH2- anions in the molar ratio 1:3. The borohydride anion has an ideal tetrahedral geometry, while the H−N−H bond angle equals ∼106°. The Li configuration around B is nearly tetrahedral, while that around N resembles a distorted saddlelike configuration, similar to those in LiBH4 and LiNH2, respectively.
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