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Abstract The starting point for this work was a set of crystal structures containing the motif of interaction between methyl groups in homodimers. Two structures were selected for which QTAIM, NCI and NBO analyses suggested an attractive interaction. However, the calculated interaction energy was negative for only one of these systems. The ability of methyl groups to interact with one another is then examined by DFT calculations. A series of (CH3PnHCH3)2homodimers were allowed to interact with each other for a range of Pn atoms N, P, As, and Sb. Interaction energies of these C⋅⋅⋅C tetrel‐bonded species were below 1 kcal/mol, but could be raised to nearly 3 kcal/mol if the C atom was changed to a heavier tetrel. A strengthening of the C⋅⋅⋅C intermethyl bonds can also be achieved by introducing an asymmetry via an electron‐withdrawing substituent on one unit and a donor on the other. The attractions between the methyl and related groups occur in spite of a coulombic repulsion between σ‐holes on the two groups. NBO, AIM, and NCI tools must be interpreted with caution as they can falsely suggest bonding when the potentials are repulsive.
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This content will become publicly available on February 10, 2026
Interplay between Two Structure Types in the Incommensurately Modulated A 14+2/3 Ta 8 Se 46+2/3 Compounds (A = Rb, Cs)
- Award ID(s):
- 2305731
- PAR ID:
- 10618848
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Inorganic Chemistry
- Volume:
- 64
- Issue:
- 5
- ISSN:
- 0020-1669
- Page Range / eLocation ID:
- 2403 to 2414
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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