Charge Transfer via the Dative N−B Bond and Dihydrogen Contacts. Experimental and Theoretical Electron Density Studies of Four Deltahedral Boranes

Mebs, Stefan; Kalinowski, Roman; Grabowsky, Simon; Förster, Diana; Kickbusch, Rainer; Justus, Eugen; Morgenroth, Wolfgang; Paulmann, Carsten; Luger, Peter; Gabel, Detlef; Lentz, Dieter (2011). Charge Transfer via the Dative N−B Bond and Dihydrogen Contacts. Experimental and Theoretical Electron Density Studies of Four Deltahedral Boranes. Journal of physical chemistry. A, 115(8), pp. 1385-1395. American Chemical Society 10.1021/jp109576a

[img] Text
014_Mebs2011_JPhysChemA.pdf - Published Version
Restricted to registered users only
Available under License Publisher holds Copyright.

Download (3MB) | Request a copy

In an approach combining high resolution X-ray diffraction at low temperatures with density functional calculations, two closo-borates, B12H12(2-) (1) and B10H10(2-) (2), and two arachno-boranes, B10H12L2 (L = amine (3) or acetonitrile (4)), are studied by means of Atoms In Molecules (AIM) theory and Electron Localizability Indicator (ELI-D). The charge transfer via the dative N-B bonds in the arachno-boranes and via dihydrogen contacts in the closo-borates is quantified. The dative N-B bond in 4 is significantly shorter and stronger than that in 3 and in small N-B Lewis acid base adducts from the literature. It is even shorter in the gas phase than in the crystal environment in contrast to the bond shortening in the crystal generally found for N-B Lewis acid-base adducts. Furthermore, the calculated charge transfer in terms of AIM charges is opposite to the expected N → B direction but still weak as found for all other N-B bonds. The intramolecular charge redistributions due to intermolecular interactions are quantified by the AIM and ELI-D analysis of contact ion pairs. The latter method gives a deeper understanding of delocalization effects in the borane cages as well as in the counterions. Since dihydrogen bonds are rarely found in crystal structures, one focus was directed to the topologies of the large number of 58 experimentally found contacts of this type. The analysis reveals that the electron density at the bond critical point, the corresponding Laplace function, and the curvature along the bond path (λ3) show a behavior that clearly discriminates these interactions from classical hydrogen bonds, confirming earlier theoretical findings.

Item Type:

Journal Article (Original Article)

Division/Institute:

08 Faculty of Science > Departement of Chemistry and Biochemistry

UniBE Contributor:

Grabowsky, Simon

Subjects:

500 Science > 570 Life sciences; biology
500 Science > 540 Chemistry

ISSN:

1089-5639

Publisher:

American Chemical Society

Language:

English

Submitter:

Simon Grabowsky

Date Deposited:

06 Feb 2020 11:32

Last Modified:

06 Feb 2020 11:32

Publisher DOI:

10.1021/jp109576a

BORIS DOI:

10.7892/boris.138490

URI:

https://boris.unibe.ch/id/eprint/138490

Actions (login required)

Edit item Edit item
Provide Feedback