We evaluate the correlation between binding energy (BE) and electron density
- Award ID(s):
- 2102461
- NSF-PAR ID:
- 10430208
- Date Published:
- Journal Name:
- Molecules
- Volume:
- 28
- Issue:
- 1
- ISSN:
- 1420-3049
- Page Range / eLocation ID:
- 263
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract ρ (r )J. Comput. Chem .,2019 ,40 , 2868). As an efficient tool, we use local stretching force constantderived from the local vibrational mode theory of Konkoli and Cremer. We compare the physical nature of BE versus , and provide an important explanation for cases with significant deviation in the BE– relation as well as in the BE– ρ (r )is a local measure of hydrogen bond strength covering different aspects of bonding. A simplified and unified description of hydrogen bonding is not always possible and needs an in‐depth understanding of the systems involved. -
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Abstract Modern vibrational spectroscopy is more than just an analytical tool. Information about the electronic structure of a molecule, the strength of its bonds, and its conformational flexibility is encoded in the normal vibrational modes. On the other hand, normal vibrational modes are generally delocalized, which hinders the direct access to this information, attainable only via local vibration modes and associated local properties. Konkoli and Cremer provided an ingenious solution to this problem by deriving local vibrational modes from the fundamental normal modes, obtained in the harmonic approximation of the potential, via mass‐decoupled Euler–Lagrange equations. This review gives a general introduction into the local vibrational mode theory of Konkoli and Cremer, elucidating how this theory unifies earlier attempts to obtain easy to interpret chemical information from vibrational spectroscopy: (a) the local mode theory furnishes bond strength descriptors derived from force constant matrices with a physical basis, (b) provides the highly sought after extension of the Badger rule to polyatomic molecules, (c) and offers a simpler way to derive localized vibrations compared to the complex route via overtone spectroscopy. Successful applications are presented, including a new measure of bond strength, a new detailed analysis of infrared/Raman spectra, and the recent extension to periodic systems, opening a new avenue for the characterization of bonding in crystals. At the end of this review the LMODEA software is introduced, which performs the local mode analysis (with minimal computational costs) after a harmonic vibrational frequency calculation optionally using measured frequencies as additional input.
This article is categorized under:
Structure and Mechanism > Molecular Structures
Theoretical and Physical Chemistry > Spectroscopy
Software > Quantum Chemistry
Electronic Structure Theory > Ab Initio Electronic Structure Methods
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/molecules28010263
