Point energy quantumwise
1 – 3 Many kinds of high-pressure electrides have been theoretically predicted and experimentally characterized to date. 1 – 3 Its physicochemical properties under high pressures have been thoroughly scrutinized by Miao, Hoffmann, and their co-workers. Since the electron off the nuclei occupies quantized levels of the voids and exists in ways that are quite chemical, one can call it an anionic electron or interstitial quasiatom (ISQ). One may define the electride as an ionic compound in which an electron resides in an interstitial space and behaves as if it were an anion. Signatures of bonding and anti-bonding orbital interactions can be witnessed. Detailed analyses on the band structures, the projected density of states, and crystal orbitals at the Γ point in the reciprocal space hint at the potential of forming a bond between the non-nuclear electron density and the neighboring atoms. This finding agrees with a simple Zintl picture, which suggests a valence electron count of. Since the electron densities off the atoms are confined in crystalline voids, separated from each other, and behaving as an anion, Li 17Tt 4 can be identified as a potential zero-dimensional electride. By means of the first-principles electronic structure calculations, which are followed by the analyses of the electron localization function (ELF), Bader charges, and spin density, we observe non-nuclear maxima of the ELF, electron density, and spin density. In the beginning of this paper, the structural complexity of Li 17Tt 4 is gradually stripped away using the concept of the M26 cluster found in γ-brass structures and a Tt-centered polyhedral representation. The lithium-richest phase in the binary Li-Tt system (Tt = Si, Ge, Sn, and Pb) has a stoichiometry of Li 17Tt 4.