In:
ChemPhysChem, Wiley, Vol. 7, No. 5 ( 2006-05-12), p. 1136-1141
Abstract:
Optimized structures, with all real frequencies, of superalkali superhalides (Li 3 ) + (SH) − (SH=LiF 2 , BeF 3 , and BF 4 ), are obtained, for the first time, at the B3LYP/aug‐cc‐pVDZ and MP2/aug‐cc‐pVDZ computational levels. These superalkali superhalides possess three characteristics that are significantly different from normal alkali halides. 1) They have a variety of structures, which come from five bonding mode types: edge–face, edge–edge, face–face, face–edge, and staggered face–edge. We find that the bonding mode type closely correlates with the Li 3 SH bond energy. 2) The valence electrons on the Li 3 ring are pushed out by the (SH) − anion, and become excess electrons, conferring alkalide or electride characteristics on these Li 3 SH species, depending on the bonding mode type. 3) The highest occupied molecular orbital of each Li 3 SH species is a doubly occupied delocalized σ bonding orbital on the Li 3 ring, which indicates its aromaticity. It is noticeable that the maximum negative nucleus‐independent chemical shift value (about −10 ppm) moves out from the center of the Li 3 ring, owing to repulsion by the SH − anion. We find that these superalkali superhalides are not only complicated “supermolecules”, but are also a new type of alkalide or electride, with aromaticity.
Type of Medium:
Online Resource
ISSN:
1439-4235
,
1439-7641
DOI:
10.1002/cphc.200600014
Language:
English
Publisher:
Wiley
Publication Date:
2006
detail.hit.zdb_id:
2025223-7
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