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Title: Diboron Bonds Between BX 3 (X=H, F, CH 3 ) and BYZ 2 (Y=H, F; Z=CO, N 2 , CNH)
Abstract

The ability of B atoms on two different molecules to engage with one another in a noncovalent diboron bond is studied by ab initio calculations. Due to electron donation from its substituents, the trivalent B atom of BYZ2(Z=CO, N2, and CNH; Y=H and F) has the ability to in turn donate charge to the B of a BX3molecule (X=H, F, and CH3), thus forming a B⋅⋅⋅B diboron bond. These bonds are of two different strengths and character. BH(CO)2and BH(CNH)2, and their fluorosubstituted analogues BF(CO)2and BF(CNH)2, engage in a typical noncovalent bond with B(CH3)3and BF3, with interaction energies in the 3–8 kcal/mol range. Certain other combinations result in a much stronger diboron bond, in the 26–44 kcal/mol range, and with a high degree of covalent character. Bonds of this type occur when BH3is added to BH(CO)2, BH(CNH)2, BH(N2)2, and BF(CO)2, or in the complexes of BH(N2)2with B(CH3)3and BF3. The weaker noncovalent bonds are held together by roughly equal electrostatic and dispersion components, complemented by smaller polarization energy, while polarization is primarily responsible for the stronger ones.

 
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Award ID(s):
1954310
NSF-PAR ID:
10250175
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
ChemPhysChem
Volume:
22
Issue:
14
ISSN:
1439-4235
Page Range / eLocation ID:
p. 1461-1469
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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