Electronic Basis of Improper Hydrogen Bonding: A Subtle Balance of Hyperconjugation and Rehybridization
Florida State University · University of Wisconsin–Madison
Abstract
The X[bond]H bond length in X[bond]H...Y hydrogen bonded complexes is controlled by a balance of two main factors acting in opposite directions. "X[bond]H bond lengthening" due to n(Y)-->sigma(H[bond]X) hyperconjugative interaction is balanced by "X[bond]H bond shortening" due to increase in the s-character and polarization of the X[bond]H. When hyperconjugation dominates, X[bond]H bond elongation is reflected in a concomitant red shift of the corresponding IR stretching frequency. When the hyperconjugative interaction is weak and the X-hybrid orbital in the X[bond]H is able to undergo a sufficient change in hybridization and polarization, rehybridization dominates leading to a shortening of the X[bond]H and a…
Citation impact
- FWCI
- 43.24
- Percentile
- 100%
- References
- 39
Authors
4- IVIgor V. AlabuginCorresponding
Florida State University, University of Wisconsin–Madison
- MMMariappan Manoharan
Florida State University, University of Wisconsin–Madison
- SPScott Peabody
Florida State University, University of Wisconsin–Madison
- FWFrank Weinhold
Florida State University, University of Wisconsin–Madison
Topics & keywords
- Hyperconjugation
- Chemistry
- Hydrogen bond
- Sextuple bond
- Bond order
- Three-center two-electron bond
- Bond length
- Single bond