The assessment and application of an approach to noncovalent interactions: the energy decomposition analysis (EDA) in combination with DFT of revised dispersion correction (DFT-D3) with Slater-type orbital (STO) basis set

In the present study, microsolvation and interaction of the CH[Formula: see text] cation with He[Formula: see text] clusters are investigated by means of ab initio calculations at MP2/aug-cc-pVTZ and QCISD/aug-cc-pVTZ levels. Stabilization energies of the studied complexes including basis set superposition error (BSSE) and zero point energy (ZPE) corrections are in the range of [Formula: see text][Formula: see text]kJ/mol and [Formula: see text][Formula: see text]kJ/mol. A good linear correlation is found between the stabilization energy and stretching frequency shift ([Formula: see text]) in the studied complexes. According to energy decomposition analysis, it is found that polarization effects are the major source of the attraction in these complexes.

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Experimental FTIR and theoretical investigation of the molecular structure and vibrational spectra of acetanilide using DFT and dispersion correction to DFT

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633619500093 ◽

2019 ◽

Vol 18 (02) ◽

pp. 1950009 ◽

Cited By ~ 2

Author(s):

Yunusa Umar ◽

Nedal Abu-Thabit ◽

Paul Jerabek ◽

Ponnadurai Ramasami

Keyword(s):

Vibrational Spectra ◽

Density Functional ◽

Decomposition Analysis ◽

Density Functional Theory Method ◽

Molecular Structures ◽

Basis Set ◽

Potential Energy Distribution ◽

Energy Decomposition Analysis ◽

Dispersion Correction ◽

Vibrational Assignments

The FTIR spectrum of acetanilide (ACN) is recorded and analyzed. The optimized molecular structures, harmonic vibrational wavenumbers and corresponding vibrational assignments of the ACN are computationally examined by using the B3LYP density functional theory method together with the standard 6-311[Formula: see text]G([Formula: see text],[Formula: see text]) basis set. From the calculations, the ACN is predicted to exist predominantly in trans configuration with the relative energy, rotational barrier, and population of 2.8[Formula: see text]kcal/mol, 14.8[Formula: see text]kcal/mol, and 99.5%, respectively. The optimized structure shows that the amide group (CO–NH) of trans-ACN adopts a planar peptide-like conformation. The effect of the incorporation of dispersion correction to the B3LYP on the calculated equilibrium structure and vibrational spectra of ACN is investigated. The highest occupied and the lowest unoccupied molecular orbitals, IR intensities and molecular electrostatic potential results are reported. In addition, reliable vibrational assignments have been made on the basis of Potential Energy Distribution (PED) using VEDA4 program. Simulated IR spectrum are compared with the experimental FTIR and FT-Raman spectra. Energy decomposition analysis (EDA) revealed that Pauli repulsion is responsible for the increased stability of the trans over the cis isomer.

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Through-Bond and Through-Space Interactions in [2,2]Cyclophanes

Journal of the Brazilian Chemical Society ◽

10.21577/0103-5053.20210043 ◽

2021 ◽

Author(s):

Sérgio Galembeck ◽

Renato Orenha ◽

Rafael Madeira ◽

Letícia Peixoto ◽

Renato Parreira

Keyword(s):

Electron Density ◽

Noncovalent Interactions ◽

Topological Analysis ◽

Decomposition Analysis ◽

Energy Decomposition Analysis ◽

Relative Importance ◽

Energy Decomposition ◽

Covalent Contribution ◽

Pauli Repulsion ◽

Open Question

The interpretation of the distortions of the electron distribution in [2,2]cyclophanes (22-CPs) is controversial. Some studies indicate that there is an accumulation of electron density (ρ) outside the cavity of 22-CPs. The nature of through-space (ts) interaction is still under debate. The relative importance of ts and through-bond (tb) is an open question. In an attempt to clarify these points, we have investigated five 22-CPs and their corresponding toluene dimers by molecular orbitals analysis, electron density difference analysis, some topological analysis of ρ (quantum theory of atoms in molecules (QTAIM), electron localization function (ELF) and noncovalent interactions (NCI)), and energy decomposition analysis with natural orbitals for chemical valence (EDA-NOCV). ρ is concentrated inside the inter-ring region. All the analyses indicated that ts is predominant. The ts is composed by attractive dispersion and Pauli repulsion, with a small covalent contribution. Except for 1 and 6, all the compounds present inter-ring bond paths.

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VERY DIFFERENT CH3 INTERNAL ROTATION BARRIERS IN THE SYN- AND ANTI- FORMS OF THIOACETIC ACID: MICROWAVE MEASUREMENTS AND ENERGY DECOMPOSITION ANALYSIS

Proceedings of the 73rd International Symposium on Molecular Spectroscopy ◽

10.15278/isms.2018.wh07 ◽

2018 ◽

Author(s):

CJ Smith ◽

Yirong Mo ◽

Huaiyu Zhang ◽

Ken Leopold ◽

Anna Huff

Keyword(s):

Internal Rotation ◽

Decomposition Analysis ◽

Energy Decomposition Analysis ◽

Microwave Measurements ◽

Thioacetic Acid ◽

Energy Decomposition

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Energy Decomposition Analysis Reveals the Nature of Lone Pair−π Interactions with Cationic π Systems in Catalytic Acyl Transfer Reactions

Organic Letters ◽

10.1021/acs.orglett.1c01351 ◽

2021 ◽

Author(s):

Hua Hao ◽

Xiaotian Qi ◽

Weiping Tang ◽

Peng Liu

Keyword(s):

Decomposition Analysis ◽

Lone Pair ◽

Acyl Transfer ◽

Transfer Reactions ◽

Energy Decomposition Analysis ◽

Energy Decomposition ◽

Π Interactions ◽

Acyl Transfer Reactions

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Direct estimate of the internal π-donation to the carbene centre within N-heterocyclic carbenes and related molecules

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.11.294 ◽

2015 ◽

Vol 11 ◽

pp. 2727-2736 ◽

Cited By ~ 38

Author(s):

Diego M Andrada ◽

Nicole Holzmann ◽

Thomas Hamadi ◽

Gernot Frenking

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Decomposition Analysis ◽

Heterocyclic Carbenes ◽

Energy Decomposition Analysis ◽

Energy Decomposition ◽

Direct Estimate ◽

Functional Theory ◽

Bonding Analysis

Fifteen cyclic and acylic carbenes have been calculated with density functional theory at the BP86/def2-TZVPP level. The strength of the internal X→p(π) π-donation of heteroatoms and carbon which are bonded to the C(II) atom is estimated with the help of NBO calculations and with an energy decomposition analysis. The investigated molecules include N-heterocyclic carbenes (NHCs), the cyclic alkyl(amino)carbene (cAAC), mesoionic carbenes and ylide-stabilized carbenes. The bonding analysis suggests that the carbene centre in cAAC and in diamidocarbene have the weakest X→p(π) π-donation while mesoionic carbenes possess the strongest π-donation.

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