Topic
Lewis structure
About: Lewis structure is a research topic. Over the lifetime, 266 publications have been published within this topic receiving 9969 citations. The topic is also known as: Lewis dot diagram & electron dot diagram.
Papers published on a yearly basis
Papers
TL;DR: In this paper, the electronic structure of the radical CH 2 OH was analyzed via the "different hybrids for different spins" natural bond orbital (DHDS NBO) procedure, which finds separate Lewis structures for each of the spin systems.
Abstract: We have carried out ab initio UHF/6-31G* calculations on the hydroxymethyl radical, CH 2 OH, and have found the equilibrium structure to be nearly planar with barriers to internal rotation occurring at staggered and eclipsed geometries, in good agreement with experiment. The electronic structure of the radical was analyzed via the “different hybrids for different spins” natural bond orbital (DHDS NBO) procedure, which finds separate Lewis structures for each of the spin systems. The α spin Lewis structure resembles that of the anion; the β spin Lewis structure resembles the corresponding cation. This simple picture, in conjunction with Bent's rule, allows one to understand the principal electronic factors which dictate the structure of the radical CH 2 group and its torsional and inversion potentials. Charge transfer between oxygen non-bonding orbitals and the empty radical orbital in the β spin system is the dominant interaction determining the torsional potential. Smaller hyperconjugative interactions in the α spin system resemble interactions in closed-shell molecules and directly oppose the effect of radical hyperconjugation, thus illustrating the central idea that open-shell potential energy features result from competition between the two different spin systems.
2,010 citations
1,594 citations
TL;DR: Natural bond orbital (NBO) methods encompass a suite of algorithms that enable fundamental bonding concepts to be extracted from Hartree-Fock (HF), Density Functional Theory (DFT), and post-HF computations as discussed by the authors.
Abstract: Natural bond orbital (NBO) methods encompass a suite of algorithms that enable fundamental bonding concepts to be extracted from Hartree-Fock (HF), Density Functional Theory (DFT), and post-HF computations. NBO terminology and general mathematical formulations for atoms and polyatomic species are presented. NBO analyses of selected molecules that span the periodic table illustrate the deciphering of the molecular wavefunction in terms commonly understood by chemists: Lewis structures, charge, bond order, bond type, hybridization, resonance, donor–acceptor interactions, etc. Upcoming features in the NBO program address ongoing advances in ab initio computing technology and burgeoning demands of its user community by introducing major new methods, keywords, and electronic structure system/NBO communication enhancements. © 2011 John Wiley & Sons, Ltd.
1,486 citations
TL;DR: An exceptionally simple algebraic construction allows for defining atomic core and valence orbitals, polarized by the molecular environment, which can exactly represent self-consistent field wave functions, providing an unbiased and direct connection between quantum chemistry and empirical chemical concepts.
Abstract: Modern quantum chemistry can make quantitative predictions on an immense array of chemical systems. However, the interpretation of those predictions is often complicated by the complex wave function expansions used. Here we show that an exceptionally simple algebraic construction allows for defining atomic core and valence orbitals, polarized by the molecular environment, which can exactly represent self-consistent field wave functions. This construction provides an unbiased and direct connection between quantum chemistry and empirical chemical concepts, and can be used, for example, to calculate the nature of bonding in molecules, in chemical terms, from first principles. In particular, we find consistency with electronegativities (χ), C 1s core-level shifts, resonance substituent parameters (σR), Lewis structures, and oxidation states of transition-metal complexes.
921 citations
1 Jan 1988
TL;DR: In the last century, qualitative structural inferences based on stoichiometry, number of isomers and other lines of indirect chemical evidence were giving rise to models of molecular connectivity and geometry (e.g., the tetrahedral carbon atom of van-t Hoff and Le Bel) that underlie current electronic theories of valence as mentioned in this paper.
Abstract: As the “Coulomb explosion”1 and other techniques add to our knowledge of molecular geometry, it is appropriate to recall the debt of gratitude that many theoretical concepts owe to structural studies. Indeed, new structural data have often provided the principal stimulus for new chemical concepts. Even prior to the discovery of the electron in the last century, qualitative structural inferences based on stoichiometry, number of isomers, and other lines of indirect chemical evidence were giving rise to models of molecular connectivity and geometry (e.g., the tetrahedral carbon atom of van’t Hoff and Le Bel2) that underlie current electronic theories of valence.
450 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 11 |
| 2020 | 6 |
| 2019 | 9 |
| 2018 | 11 |
| 2017 | 11 |
| 2016 | 22 |