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Title: Triel Bonds with Methyl Groups as Electron Donors. A Pentacoordinate Carbon Atom
Abstract The triel bond (TrB) formed between Be(CH3)2/Mg(CH3)2and TrX3(Tr=B, Al, and Ga; X=H, F, Cl, Br, and I) is investigated via the MP2/aug‐cc‐pVTZ(PP) quantum chemical protocol. The C atoms of the methyl groups in M(CH3)2are characterized by a negative electrostatic potential and act as an electron donor in a triel bond with the π‐hole above the Tr atom of planar TrX3. The interaction energy spans a wide range between −2 and −69 kcal/mol. Mg(CH3)2forms a stronger TrB than does Be(CH3)2, which comports with the more negative electrostatic potential on its methyl groups. Some of the complexes involving Mg display a high degree of transfer of the methyl group from Mg to Tr, which is accompanied by an inversion of the bridging methyl and a sizable pyramidalization of the TrX3unit. The geometries of these complexes have the properties of the long sought pentacoordinate C which has eluded identification and characterization in the past.  more » « less
Award ID(s):
1954310
PAR ID:
10642623
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
ChemPhysChem
Volume:
26
Issue:
3
ISSN:
1439-4235
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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