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Journal articles on the topic 'Natural bond orbital (NBO)'

Author: Grafiati

Published: 4 June 2021

Last updated: 2 February 2022

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1

Glendening, Eric D., Clark R. Landis, and Frank Weinhold. "NBO 6.0: Natural bond orbital analysis program." Journal of Computational Chemistry 34, no. 16 (2013): 1429–37. http://dx.doi.org/10.1002/jcc.23266.

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2

Li, Xiao-Hong, Rui-Zhou Zhang, and Xian-Zhou Zhang. "Theoretical investigation of some N-nitrosodiphenylamine biological molecules — A natural bond orbital (NBO) study." Canadian Journal of Chemistry 89, no. 10 (2011): 1230–35. http://dx.doi.org/10.1139/v11-084.

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Theoretical study of several N-nitrosodiphenylamine biological molecules has been performed using quantum computational ab initio RHF and density functional B3LYP and B3PW91 methods with 6–311G++(d,p) basis set. Geometries obtained from density functional theory (DFT) calculations were used to perform Natural bond orbital (NBO) analysis. The p characters of two nitrogen natural hybrid orbitals (NHOs) σN3−N2 increase with increasing σp values of the substituents on the benzene, which results in a lengthening of the N3–N2 bond. The p characters of oxygen NHO σO1−N2 and nitrogen NHO σO1−N2 bond o

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3

Glendening, Eric D., Clark R. Landis, and Frank Weinhold. "Erratum: NBO 6.0: Natural bond orbital analysis program." Journal of Computational Chemistry 34, no. 24 (2013): 2134. http://dx.doi.org/10.1002/jcc.23366.

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4

Momeni, Mohammad R., Lisa Shulman, Eric Rivard, and Alex Brown. "Interplay of donor–acceptor interactions in stabilizing boron nitride compounds: insights from theory." Physical Chemistry Chemical Physics 17, no. 25 (2015): 16525–35. http://dx.doi.org/10.1039/c5cp01993a.

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The chemical bonds in donor–acceptor stabilized linear and cyclic (BN)<sub>n</sub> (n = 1–3) adducts are examined using natural bond orbital (NBO), atoms-in-molecules (AIM), and energy decomposition (EDA-NOCV) analyses.

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5

Monajjemi, Majid, Halleh H. Haeri, and Malihe T. Azad. "Theoritical ab initio study of Internal Rotation Barriers, Structures Stabilities and Population of Formamide." Journal of Chemical Research 2002, no. 8 (2002): 403–6. http://dx.doi.org/10.3184/030823402103172473.

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The internal rotational barriers for formamide are calculated in gas and solution phases (acetonitrile) at the HF/6-31G* (16.64 and 16.18 kcal/mol, respectively) and MP2/6-31G* (16.86 and 16.71 kcal/ mol, respectively) level of theory. Calculated parameters are compared with experimental data and there is a good agreement between them. Orbital populations are obtained by MPA (mulliken population analysis) and NPA (natural population analysis) methods and bond energies are calculated by the NBO method (natural bond orbitals). The distribution of atomic charges are also given. These calculation

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6

Joshi, Bhawani Datt, Poonam Tandon, and Sudha Jain. "Differential Scanning Calorimetry, NBO and Hyperpolarizability Analysis of Yohimbine Hydrochloride." Himalayan Physics 3 (December 26, 2012): 44–49. http://dx.doi.org/10.3126/hj.v3i0.7276.

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Yohimbine (C21H27N2O3) is one of the most important indole alkaloid. Differential scanning calorimetry, natural bond orbital (NBO) analysis and dipole moment with hyperpolarizability have been performed for molecular characterization. Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed using NBO analysis. The results show that charge in electron density (ED) in the ?* and ?* anti bonding orbitals and E(2) energies confirms the occurrence of intra molecular charge transfer (ICT) within the molecule.The Himalayan PhysicsVol. 3, No. 32012

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7

Li, Xiao-Hong, Geng-Xin Yin, and Xian-Zhou Zhang. "Natural bond orbital (NBO) population analysis of some benzyl nitrites." Journal of Molecular Structure: THEOCHEM 957, no. 1-3 (2010): 61–65. http://dx.doi.org/10.1016/j.theochem.2010.07.005.

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8

Matin, Mohammad A., Mohammad Alauddin, Tapas Debnath, M. Saiful Islam, and Mohammed A. Aziz. "DFT and TD-DFT Study of [Tris(dithiolato)M]3- Complexes[M= Cr, Mn and Fe]: Electronic Structures, Properties and Analyses." Dhaka University Journal of Science 67, no. 1 (2019): 63–68. http://dx.doi.org/10.3329/dujs.v67i1.54576.

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Using Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TD-DFT) methods, transition metal complexes of benzene-1, 2-dithiolate (L2-) ligand from Cr to Fe have been studied theoretically. The ground state geometries, binding energies, UV-Visible spectra (UV-Vis), frontier molecular orbitals (FMOs) analysis, charge analysis and natural bond orbital (NBO) have been calculated. The structural parameters are in good accord with the experimental data. The metal-ligand binding energies are one (1) order of magnitude higher than the physisorption energy of a benzene-1, 2-dt

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9

Safonova, Liubov P., Michail G. Kiselev, and Irina V. Fedorova. "Complexes of sulfuric acid with N,N-dimethylformamide: An ab initio investigation." Pure and Applied Chemistry 85, no. 1 (2012): 225–36. http://dx.doi.org/10.1351/pac-con-12-01-04.

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The (H2SO4)2, H2SO4-DMF, and (H2SO4)2-DMF complexes have been investigated, using the B3LYP functional with cc-pVQZ basis set. The characteristics of structure and energetics for binary complexes of sulfuric acid with dimethylformamide (DMF) have been obtained for the first time. The H-bond formation both between molecules of sulfuric acid as well as sulfuric acid-DMF were studied, on the basis of Weinhold’s natural bond orbital (NBO) analysis. It was shown that the H-bond formation between sulfuric acid and DMF molecules is stronger than ones for the acids dimer. The value of charge transfer

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10

Laconsay, Croix J., Ka Yi Tsui, and Dean J. Tantillo. "Tipping the balance: theoretical interrogation of divergent extended heterolytic fragmentations." Chemical Science 11, no. 8 (2020): 2231–42. http://dx.doi.org/10.1039/c9sc05161a.

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We interrogate a type of heterolytic fragmentation called a ‘divergent fragmentation’ using density functional theory (DFT), natural bond orbital (NBO) analysis, ab initio molecular dynamics (AIMD), and external electric field (EEF) calculations.

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11

Nelson, Joel T., and William J. Pietro. "Natural bond orbital (NBO) analysis of substituent effects in borazine derivatives." Inorganic Chemistry 28, no. 3 (1989): 544–48. http://dx.doi.org/10.1021/ic00302a031.

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12

Gangadharan, Rubarani P., and S. Sampath Krishnan. "Natural Bond Orbital (NBO) Population Analysis of 1-Azanapthalene-8-ol." Acta Physica Polonica A 125, no. 1 (2014): 18–22. http://dx.doi.org/10.12693/aphyspola.125.18.

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13

Rivera, Augusto, Juan Manuel Uribe, Jaime Ríos-Motta, Hector Jairo Osorio, and Michael Bolte. "Evidence for stereoelectronic effects in the N—C—N group of 8,10,12-triaza-1-azoniatetracyclo[8.3.1.18,12.02,7]pentadecane 4-nitrophenolate 4-nitrophenol monosolvate from the protonation of aminal (2R,7R)-1,8,10,12-tetraazatetracyclo[8.3.1.18,12.02,7]pentadecane: X-ray and natural bond orbital analysis." Acta Crystallographica Section C Structural Chemistry 71, no. 4 (2015): 284–88. http://dx.doi.org/10.1107/s2053229615004829.

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The title molecular salt, C11H21N4+·C6H4NO3−·C6H5NO3, (II), crystallizes with two independent three-component aggregates in the asymmetric unit. In the cations, the cyclohexane rings fused to the cage azaadamantane systems both adopt a chair conformation. In the crystal structure, the aggregates are connected by C—H...O hydrogen bonds, forming a supramolecular unit enclosing anR44(24) ring motif. These units are linkedviaC—H...O and C—H...N hydrogen bonds, forming a three-dimensional network. Even hydrogen-bond formation to one of the N atoms is enough to induce structural stereoelectronic eff

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14

Bihain, Murielly Fernanda Ribeiro, Raissa Santos Sousa, Sílvio Quintino de Aguiar Filho, and Douglas Henrique Pereira. "Cálculos teóricos para elucidação eletrônica de barreiras rotacionais: teoria e aplicações." Journal of Biotechnology and Biodiversity 8, no. 2 (2020): 136–47. http://dx.doi.org/10.20873/jbb.uft.cemaf.v8n2.bihain.

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Cálculos teóricos de estrutura eletrônica são ferramentas da química teórica. Sua importância se estende desde a análises de rotação, hiperconjugação, efeitos estéricos a cálculos de localização de orbitais, nível de energia e interação entre orbitais ligantes e antiligantes. As teorias como Natural Bond Orbital (NBO), Quantum Theory of Atoms in Molecules (QTAIM), e Energetic Decomposition Analysis (EDA), são exemplos de ferramentas teóricas que descrevem a estrutura eletrônica de moléculas e sólidos. Neste contexto o objetivo do artigo foi descrever as abordagens teóricas do NBO, EDA e QTAIM

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15

Brenner, Valérie, Eric Gloaguen, and Michel Mons. "Rationalizing the diversity of amide–amide H-bonding in peptides using the natural bond orbital method." Physical Chemistry Chemical Physics 21, no. 44 (2019): 24601–19. http://dx.doi.org/10.1039/c9cp03825f.

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Natural bond orbital (NBO) analysis of electron delocalization in a series of capped isolated peptides is used to diagnose amide–amide H-bonding and backbone-induced hyperconjugative interactions, and to rationalize their spectral effects.

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16

Abbaz, Tahar, Amel Bendjeddou, and Didier Villemin. "Molecular structure, HOMO, LUMO, MEP, natural bond orbital analysis of benzo and anthraquinodimethane derivatives." Pharmaceutical and Biological Evaluations 5, no. 2 (2018): 27. http://dx.doi.org/10.26510/2394-0859.pbe.2018.04.

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Objective: Optimized molecular structures have been investigated by DFT/B3LYP method with 6-31G (d,p) basis set. Stability of Benzo and anthraquinodimethane derivatives 1-4, hyperconjugative interactions, charge delocalization and intramolecular hydrogen bond has been analyzed by using natural bond orbital (NBO) analysis. Electronic structures were discussed and the relocation of the electron density was determined. Molecular electrostatic potential (MEP), local density functional descriptors has been studied. Nonlinear optical (NLO) properties were also investigated. In addition, frontier mol

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17

Kazeminejad, Zahra, Abolfazl Shiroudi, Khalil Pourshamsian, Farhad Hatamjafari, and Ahmad Oliaey. "Understanding the isomerization kinetics in the gas phase of a triazole-3-thione derivative: A theoretical approach." Journal of the Serbian Chemical Society 84, no. 9 (2019): 975–89. http://dx.doi.org/10.2298/jsc181208013k.

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The isomerization reactions of the 4-amino-5-methyl-2,4-dihydro- -3H-1,2,4-triazole-3-thione were studied using the B3LYP and M06-2x, as well as the CBS-QB3 theoretical methods. The measured energy profiles were complemented with kinetic rate constants using the transition state theory (TST). Based on the isomers geometries optimized using the CBS-QB3 method, a natural bond orbital (NBO) analysis shows that the stabilization energies of non-bonding lone-pair orbitals [LP(e)S7] to the ?*N2?C3 antibonding orbital increase from isomers 1 to 2. Moreover, the LP(e)S7 ? ?*N2?C3 delocalizations could

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18

Glendening, Eric D., and Frank Weinhold. "Pauling’s Conceptions of Hybridization and Resonance in Modern Quantum Chemistry." Molecules 26, no. 14 (2021): 4110. http://dx.doi.org/10.3390/molecules26144110.

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We employ the tools of natural bond orbital (NBO) and natural resonance theory (NRT) analysis to demonstrate the robustness, consistency, and accuracy with which Linus Pauling’s qualitative conceptions of directional hybridization and resonance delocalization are manifested in all known variants of modern computational quantum chemistry methodology.

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19

Mitrasinovic, Petar M. "Acrylonitrile (AN)Cu9(100) interfaces: Electron distribution and nature of bonded interactions." Canadian Journal of Chemistry 81, no. 6 (2003): 542–54. http://dx.doi.org/10.1139/v03-043.

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There is a fundamental interest in the investigation of the interfacial interactions and charge migration processes between organic molecules and metallic surfaces from a theoretical standpoint. Quantum mechanical (QM) concepts of bonding are contrasted, and the vital importance of using combined QM methods to explore the nature of the interfacial interactions is established. At the one-electron level, the charge distribution and nature of bonded interactions at the ANCu9(100) (neutral and charged (1)) interfaces are investigated by both the Becke (B) Vosko (V) Wilk (W) Nusair (N)/DZVP

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20

Yuan, Chengqian, Haiming Wu, Meiye Jia, Peifeng Su, Zhixun Luo, and Jiannian Yao. "A theoretical study of weak interactions in phenylenediamine homodimer clusters." Physical Chemistry Chemical Physics 18, no. 42 (2016): 29249–57. http://dx.doi.org/10.1039/c6cp04922b.

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Utilizing dispersion-corrected density functional theory (DFT) calculations, we demonstrate the weak intermolecular interactions of phenylenediamine dimer (pdd) clusters, emphasizing the local lowest energy structures and decomposition of interaction energies by natural bond orbital (NBO) and atoms in molecule (AIM) analyses.

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21

Gnanasekar, Sharon Priya, and Elangannan Arunan. "A Detailed Classification of Three-Centre Two-Electron Bonds." Australian Journal of Chemistry 73, no. 8 (2020): 767. http://dx.doi.org/10.1071/ch19557.

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We evaluate the three-centre two-electron (3c-2e) bonds using atoms in molecules (AIM) and natural bond orbital (NBO) theoretical analyses. They have been classified as ‘open (V)’ or ‘closed (Δ)’, depending on how the three centres were bonded. Herein, we show that they could be classified as V, L, Δ, Y, T and I (linear) arrangements depending on the way the three centres are bonded. These different structures are found in B2H6 (V), CH5+ (V), Me-C2H2+ (L), B3+ (Δ), C3H3+ (Δ), H3+ (Y), 2-norbornyl+ (T), SiH5+ (T), and Al2H7− (I). Our results suggest that CH3Li2+ does not contain a 3c-2e bond ac

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22

Xiao-Hong, Li, Tang Zheng-Xin, and Zhang Xian-Zhou. "Natural bond orbital (NBO) population analysis of para-substituted S-Nitroso-thiophenols." Journal of Molecular Structure: THEOCHEM 900, no. 1-3 (2009): 50–54. http://dx.doi.org/10.1016/j.theochem.2008.12.022.

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23

Oziminski, Wojciech P., and Tadeusz M. Krygowski. "Natural bond orbital (NBO) analysis of the angular group induced bond alternation (AGIBA) substituent effect." Journal of Physical Organic Chemistry 23, no. 6 (2010): 551–56. http://dx.doi.org/10.1002/poc.1647.

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24

Fonseca, Tânia A. O., Matheus P. Freitas, Rodrigo A. Cormanich, Teodorico C. Ramalho, Cláudio F. Tormena, and Roberto Rittner. "Computational evidence for intramolecular hydrogen bonding and nonbonding X···O interactions in 2'-haloflavonols." Beilstein Journal of Organic Chemistry 8 (January 19, 2012): 112–17. http://dx.doi.org/10.3762/bjoc.8.12.

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The conformational isomerism and stereoelectronic interactions present in 2'-haloflavonols were computationally analyzed. On the basis of the quantum theory of atoms in molecules (QTAIM) and natural bond orbital (NBO) analysis, the conformer stabilities of 2'-haloflavonols were found to be dictated mainly by a C=O···H–O intramolecular hydrogen bond, but an unusual C–F···H–O hydrogen-bond and intramolecular C–X···O nonbonding interactions are also present in such compounds.

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25

Danaie, Elmira, Shiva Masoudi, and Nasrin Masnabadi. "A Computational Study of the Conformational Behavior of 2,5-Dimethyl- 1,4-dithiane-2,5-diol and Analogous S and Se: DFT and NBO Study." Letters in Organic Chemistry 17, no. 10 (2020): 749–59. http://dx.doi.org/10.2174/1570178617666200129144750.

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Conformational behaviors of 2,5-dimethyl-1,4-dithiane-2,5-diol (compound 1), 2,5- dimethyl-1,4-dithiane-2,5-dithiol (compound 2) and 2,5-dimethyl-1,4-dithiane-2,5-diselenol (compound 3) were investigated by the B3LYP/6-311+G **, the M06-2X/aug-ccpvdz levels of theory and natural bond orbital NBO analysis. The structures and the structural parameters of the mentioned molecules were optimized by the B3LYP and the M06-2X methods. We assessed the roles and contributions of the effective factors in the conformational properties of the mentioned compounds by means of the B3LYP and M06-2X levels of t

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26

Joshi, Bhawani Datt, and Manoj Kumar Chaudhary. "NBO, nonlinear optical and thermodynamic properties of 10-Acetyl-10H-phenothiazine 5-oxide." BIBECHANA 15 (December 19, 2017): 131–39. http://dx.doi.org/10.3126/bibechana.v15i0.18385.

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In this paper, natural bond orbital (NBO) analysis, nonlinear optical and the thermodynamic properties of 10-Acetyl-10H-phenothiazine 5-oxide have been analyzed by employing density functional theory level employing 6-311++G(d,p) basis set. NBO analysis reveals that the intra- intermolecular charge transfer occurs within the molecule leading to the stabilization. The predicted nonlinear optical properties (NLO) like; polarizability and first hyperpolarizabiliy support that the molecule could attract the interests for future investigation.BIBECHANA 15 (2018) 131-139

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27

Chandra, Asit K., and Thérèse Zeegers-Huyskens. "Theoretical Investigation of the Cooperativity in CH3CHO·2H2O, CH2FCHO·2H2O, and CH3CFO·2H2O Systems." Journal of Atomic, Molecular, and Optical Physics 2012 (July 29, 2012): 1–8. http://dx.doi.org/10.1155/2012/754879.

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The hydrogen bond interaction between CH3CHO, CH2FCHO, and CH3CFO and two water molecules is investigated at the B3LYP/6-311++G(d,p) level. The results are compared with the complexes involving the same carbonyl derivatives and one water molecule. The calculations involve the optimization of the structure, the harmonic vibrational frequencies, and relevant NBO (natural bond orbital) parameters such as the NBO charges, the occupation of antibonding orbitals, and intra- and intermolecular hyperconjugation energies. Two stable cyclic structures are predicted. The two structures are stabilized by

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28

Jiao, Yinchun, and Frank Weinhold. "NBO/NRT Two-State Theory of Bond-Shift Spectral Excitation." Molecules 25, no. 18 (2020): 4052. http://dx.doi.org/10.3390/molecules25184052.

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We show that natural bond orbital (NBO) and natural resonance theory (NRT) analysis methods provide both optimized Lewis-structural bonding descriptors for ground-state electronic properties as well as suitable building blocks for idealized “diabatic” two-state models of the associated spectroscopic excitations. Specifically, in the framework of single-determinant Hartree-Fock or density functional methods for a resonance-stabilized molecule or supramolecular complex, we employ NBO/NRT descriptors of the ground-state determinant to develop a qualitative picture of the associated charge-transfe

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29

Subramaniyan, Vasudevan, Ashok Kumar, Anbarasu Govindaraj, and Ganesan Mani. "Crystal structure and DFT analyses of a pentacoordinated PCP pincer nickel(II) complex." Acta Crystallographica Section C Structural Chemistry 75, no. 6 (2019): 734–39. http://dx.doi.org/10.1107/s2053229619006211.

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The reaction of NiCl2 with 1,3-bis[(diphenylphosphanyl)methyl]hexahydropyrimidine in the presence of 2,6-dimethylphenyl isocyanide and KPF6 afforded a new pentacoordinated PCP pincer NiII complex, namely {1,3-bis[(diphenylphosphanyl)methyl]hexahydropyrimidin-2-yl-κN 2}(2,6-dimethylphenyl isocyanide-κC)nickel(II) hexafluoridophosphate 0.70-hydrate, [Ni(C9H9N)(C30H30ClN2P2)]PF6·0.7H2O or [NiCl{C(NCH2PPh2)2(CH2)3-κ3 P,C,P′}(Xylyl-NC)]PF6·0.7H2O, in very good yield. Its X-ray structure showed a distorted square-pyramidal geometry and the compound does not undergo dissociation in solution, as shown

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30

PARVEEN, SALMA, SUBOJIT DAS, ASIT K. CHANDRA, and THERESE ZEEGERS-HUYSKENS. "THEORETICAL STUDIES OF HYDROGEN BONDING INTERACTION BETWEEN TRIMETHYLAMINE AND SUBSTITUTED PHENOLS, INFLUENCE OF THE SUBSTITUENTS ON THE HYDROGEN BOND PROPERTIES AND THE VIBRATIONAL SPECTRUM." Journal of Theoretical and Computational Chemistry 07, no. 06 (2008): 1171–86. http://dx.doi.org/10.1142/s0219633608004507.

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Hydrogen bonding interactions between trimethylamine (TMA) and a series of para substituted phenols (X– C 6 H 4 OH , X = H , CH 3, NH 2, Cl , CN , and NO 2) are studied by using density functional theory with the hybrid B3LYP functional and the 6-31++G(d,p) basis set. Both electron donor and acceptor substituents (X) are chosen to study systematically the relation between the proton donor ability of the phenols and the strength of the OH … N hydrogen bond. The effect of hydrogen bonding on spectral and structural parameters and their inter relation are discussed. The natural bond orbital (NBO)

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31

Rajalakshmi, K., and S. Sharmila. "Spectroscopic Studies and Vibrational Assignments, Homo- Lumo, UV-VIS, NBO Analysis of Benzonitrile." International Journal of ChemTech Research 13, no. 3 (2020): 225–39. http://dx.doi.org/10.20902/ijctr.2019.130320.

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The Fourier transform infrared and FT-Raman spectra of Benzonitrile have been recorded in region of 4000-400 and 4000-100 cm -1 respectively. A complete assignments and analysis of fundamental vibrational modes of the molecule have been carried out. The observed fundamental modes have been compared with harmonic vibrational frequencies computed using ab initio and density functional theory calculations by employing B3LYP functional at 6-311G(d, p) level and HF/6-311G(d, p).UV-Vis spectrum of the compound has been recorded, the natural bond orbital (NBO) electronic properties, such as highest o

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32

JÍMENEZ-FABIAN and A. F. JALBOUT. "THE ORIGIN OF THE ROTATIONAL BARRIER IN DIMETHYL ETHER AND DIMETHYL SULFIDE: A THEORETICAL STUDY." Journal of Theoretical and Computational Chemistry 06, no. 03 (2007): 421–34. http://dx.doi.org/10.1142/s0219633607003210.

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The torsional potential function for methyl rotation in dimethyl ether (DME) and dimethyl sulfide (DMS) has been determined by utilizing ab initio (Hartree–Fock and MP2) and density functional theory (B3LYP, B3P86, and B3PW91) methods along with several basis sets. Natural bond orbital (NBO) analysis was also applied to investigate the origin of the rotational barrier.

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33

Xinying, Li, and Cao Xue. "Interaction and Electron Density Properties of MKr42+ (M=Cu, Ag and Au): ab initio Calculation." Australian Journal of Chemistry 64, no. 3 (2011): 339. http://dx.doi.org/10.1071/ch10373.

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Quantum chemical calculations of the structures and stabilities of the MKr42+ series at the CCSD(T) theoretical level have been performed. The role of the interaction was investigated using the natural bond orbital (NBO), Laplacian, electron density deformation, electron localization function and reduced density gradient analysis. The results show that a covalent contribution occurs in the Kr-M2+ bonding.

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34

Günay, N., H. Pir, D. Avcı, and Y. Atalay. "NLO and NBO Analysis of Sarcosine-Maleic Acid by Using HF and B3LYP Calculations." Journal of Chemistry 2013 (2013): 1–16. http://dx.doi.org/10.1155/2013/712130.

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We report a theoretical study on molecular structure, vibrational spectra, nonlinear optical (NLO), and natural bond orbital (NBO) analysis of sarcosine-maleic acid (C7H11NO6) in the ground state calculated by using the Hartree-Fock (HF) and density functional method (DFT/B3LYP) with 6–31++G(d,p) basis set. We repeat NBO calculations with 6–31G(d,p) basis set so as to see the diffuse function impact on NBO analysis. Stability of the molecule arising from hyper conjugative interactions and charge delocalization has been analyzed using NBO analysis. NBO analysis shows that there is a O–H⋯O and N

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35

Rahmawati, Sitti, Cynthia Linaya Radiman, and Muhamad Abdulkadir Martoprawiro. "Density Functional Theory (DFT) and Natural Bond Orbital (NBO) Analysis of Intermolecular Hydrogen Bond Interaction in "Phosphorylated Nata De Coco - Water"." Indonesian Journal of Chemistry 18, no. 1 (2018): 173. http://dx.doi.org/10.22146/ijc.25170.

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This study aims to study the conformation, the hydrogen bond network, and the stabilities of all the possible intermolecular interactions in phosphorylated nata de coco membrane with water (NDCF-(H2O)n, n = 1-5). Analysis of natural bond orbital (NBO) was performed to measure the relative strength of the hydrogen bonding interactions, charge transfer, particularly the interactions of n-σ * O-H and to take into account the effect on the stabilities of the molecular structure. All calculation were performed using density functional theory (DFT) method, at B3LYP functional level of theory and 6-3

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36

Trapp, Melissa L., Jonathan K. Watts, Noham Weinberg, and B. Mario Pinto. "Component analysis of the X-C-Y anomeric effect (X = O, S; Y = F, OMe, NHMe) by DFT molecular orbital calculations and natural bond orbital analysis." Canadian Journal of Chemistry 84, no. 4 (2006): 692–701. http://dx.doi.org/10.1139/v06-048.

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Six 2-Y-substituted oxacyclohexane and thiacyclohexane heterocycles (Y = F, OMe, NHMe) were examined using DFT molecular orbital calculations. Natural bond orbital (NBO) analysis of the total energy behaviour yielded the orbital-interaction factors contributing to the conformational equilibria. The dipole moments of the optimized systems were used to estimate the electrostatic contributions to the anomeric effect. The primary determinant of the X-C-Y anomeric effect was found to be the orbital interaction components associated with the combined endo- and exo-anomeric effects acting in concert

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Loncke, Paul G., Timothy A. Gadosy, and Gilles H. Peslherbe. "A theoretical study of the mechanism of 1,2-migrations in methoxysiloxycarbene." Canadian Journal of Chemistry 80, no. 3 (2002): 302–14. http://dx.doi.org/10.1139/v02-013.

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Intramolecular rearrangements of methoxysiloxycarbene (CH3OCOSiH3) have been investigated by means of ab initio molecular orbital theory and hybrid density functional theory calculations. Particular attention was paid to 1,2-silyl migration from oxygen to the carbene carbon, and to the analogous 1,2-methyl migration for comparison. A combination of frontier molecular orbital (FMO) theory, natural bond orbital (NBO) analysis, and the theory of atoms in molecules (AIM) were used to shed light on the mechanistic details of these rearrangements. The present analyses clearly indicate that 1,2-silyl

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38

Kavousi, Hossein, Abdolreza Rezaeifard, Heidar Raissi, and Maasoumeh Jafarpour. "A DFT investigation of axial N-donor ligands effects on the high valent manganese-oxo meso-tetraphenyl porphyrin." Journal of Porphyrins and Phthalocyanines 19, no. 05 (2015): 651–62. http://dx.doi.org/10.1142/s1088424615500029.

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The effect of different electronic and structural nitrogen donors (L) on the N ( ax )- Mn - O properties in the high valent manganese-oxo meso-tetraphenylporphyrin intermediate is investigated by the density functional B3LYP method with 6-31g* basis set. The geometric structures, frontier molecular orbitals, thermodynamic parameters and physical properties such as chemical potential and chemical hardness of [( TPP )( L ) MnO ]+ complexes in the gas phase as well as water solution are calculated. Our theoretical results confirm that the Mn - O distances in [( TPP )( L ) MnO ]+ species decrease

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39

Atalay, Abdurrahman, Fatih Çelik, Yasemin Ünver, Kemal Sancak, and Kamil Kaygusuz. "Molecular Conformational Analysis, Spectroscopic Characterization, Intramolecular Hydrogen Bonding and Natural Bond Analysis of (E,Z)-2-(4- Amino-5-oxo-3-(thiophene-2-ylmethyl)-4,5-dihydro-1,2,4-triazole-1-yl)-N'- (thiophene-2-ylmethylene) Acetohydrazide." Letters in Organic Chemistry 16, no. 3 (2019): 215–25. http://dx.doi.org/10.2174/1570178615666181002141949.

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The optimized structural parameters and electronic properties including frontier molecular orbital (FMO) analysis, molecular electrostatic potential and NBO charge analysis of (E,Z)-2-(4- amino-5-oxo-3-(thiophene-2-ylmethyl)-4,5-dihydro-1,2,4-triazole-1-yl)-N&#039;-(thiophene-2-ylmethylene) acetohydrazide were investigated by using density functional theory (DFT) at B3LYP/6-311++G(d,p) level. The global reactivity parameters were evaluated in accordance with the energy values of HOMO and LUMO of each determined conformer. The molecule was experimentally characterized by means of FT-IR and

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40

ESRAFILI, MEHDI D., JAVAD BEHESHTIAN, and NASSER L. HADIPOUR. "15N CHEMICAL SHIFT CALCULATIONS AND NATURAL BONDING ORBITAL ANALYSES OF (BENZAMIDE)n = 1 - 6 CLUSTERS." Journal of Theoretical and Computational Chemistry 08, supp01 (2009): 973–82. http://dx.doi.org/10.1142/s0219633609005179.

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A DFT/B3LYP study was performed to calculate 15 N chemical shielding tensors in ( benzamide )n = 1-6 clusters. We found that N–H⋯O hydrogen bonds around the benzamide molecule in crystalline lattice have significant influences on the 15 N chemical shielding tensors. For ( benzamide )n clusters, the n-dependent trend in 15 N chemical shielding appears to be correlated with cooperative effects in R [N–H⋯O ] bond distance. Natural bonding orbital (NBO) analysis was used to rationalize the chemical shielding results in terms of [Formula: see text] charge delocalization effects in the benzamide clu

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Yuan, Kun, Ling Ling Lv, and Yuan Cheng Zhu. "Theoretical Study on the GeH₄•••Y (Y=He, Ne, Ar and Kr) Systems." Applied Mechanics and Materials 251 (December 2012): 346–50. http://dx.doi.org/10.4028/www.scientific.net/amm.251.346.

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MP2/aug-cc-pvtz level was used to optimize geometries of the complexes between GeH4 and Y(Y=He, Ne, Ar and Kr). The structures and electronic properties of the blue-shift hydrogen bonds complexes GeH4…Y(Y=Ar, Kr) were investigated. The calculated interaction energies with basis set super-position error (BSSE) correction revealed that the relative stabilities of the complexes in the order: GeH4…He ˂ GeH4…Ne ˂ GeH4…Ar ≈ GeH4…Kr. The calculated results showed that the interactions between GeH4 and Y（Y=He, Ne）belong to van der Waals force, and those between GeH4 and Y（Y=Ar, Kr）belong to weak hydro

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42

Li, Xiao-Hong, Hong-Ling Cui, and Rui-Zhou Zhang. "Theoretical investigation on vibrational spectroscopic and nonlinear optical activity of 1-(4-chloro phenyl)-3-(4-dimethylamino phenyl) prop-2-en-1-one." Canadian Journal of Physics 95, no. 4 (2017): 353–60. http://dx.doi.org/10.1139/cjp-2016-0684.

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The density functional theory method was used to calculate the vibrational spectrum, geometrical structure of 1-(4-chloro phenyl)-3-(4-dimethylamino phenyl) prop-2-en-1-one in the ground state. The analysis of natural bond orbital (NBO) was also performed. The infrared spectrum was obtained and interpreted by means of potential energies distributions. NBO analysis shows that electron donation from LP(1)N atom to the anti-bonding acceptor σ*(C6–C12) of the phenyl ring results in the stabilization of 43.9 kJ/mol. The predicted NLO properties show that the βtot of the title compound is larger tha

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Yuan, Kun, Hui Xue Li, Huian Tang, and Yuan Cheng Zhu. "Density Function Theory Study on the Recognition of the Urea-Based Involving Bromine Derivation Receptor for the Halogen Anions." Applied Mechanics and Materials 328 (June 2013): 850–54. http://dx.doi.org/10.4028/www.scientific.net/amm.328.850.

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The recognition mechanism of the urea-based involving Br derivation receptor (A) for the halogen anions through hydrogen bond and halogen bond was discussed by the density function Becke, three-parameter, Lee-Yang-Parr (B3LYP) method. The results showed that the guest-host recognition was performed by using four coordination weak bonds, which include two N-H...X hydrogen bonds and two C-Br...X halogen bonds (X= F-,Cl-,Br- and I-). The calculated interaction energies (ΔECP) with basis set super-position error (BSSE) correction of the four systems are-3.95, -82.43, -70.86 and 992.63 kJmol-1, res

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Devi, D. Parimala, Tom Giju, G. Praveena, and A. Abiram. "Theoretical Investigation of Intermolecular Dihydrogen Bonds in C2H2···HM and C2H4···HM (M = Li, Na and K) Complexes: A DFT and ab initio Study." Asian Journal of Chemistry 33, no. 8 (2021): 1811–18. http://dx.doi.org/10.14233/ajchem.2021.23252.

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This study aims to investigate the dihydrogen bond formation in ethyne (C2H2) and ethene (C2H4) with alkali metal hydrides (HM; M = Li, Na and K) complexes using density functional theory (DFT) and ab initio methods. It mainly focuses on the comparison of the performances of different functionals of DFT and ab initio method on the intermolecular dihydrogen bonded complexes. The geometrical parameter and energy values agree with the formation of dihydrogen bonds in the complexes. Among the ethyne and ethene complexes, the smallest dihydrogen bond distance was formed by C2H2···HK and C2H4···HK,

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Wang, Wei-Hua, Wen-Ling Feng, Wen-Liang Wang, and Ping Li. "Theoretical Insights into the Electron Capture Behavior of H2SO4···N2O Complex: A DFT and Molecular Dynamics Study." Molecules 23, no. 9 (2018): 2349. http://dx.doi.org/10.3390/molecules23092349.

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Both sulfuric acid (H2SO4) and nitrous oxide (N2O) play a central role in the atmospheric chemistry in regulating the global environment and climate changes. In this study, the interaction behavior between H2SO4 and N2O before and after electron capture has been explored using the density functional theory (DFT) method as well as molecular dynamics simulation. The intermolecular interactions have been characterized by atoms in molecules (AIM), natural bond orbital (NBO), and reduced density gradient (RDG) analyses, respectively. It was found that H2SO4 and N2O can form two transient molecular

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46

Geith, Janna, Thomas M. Klapötke, Richard D. Harcourt, and Peter P. Wolynec. "Ab initio Calculations and Qualitative Valence Bond Considerations for H2N-NO2 (Nitramide) and H2N-NO (Nitrosamine)." Zeitschrift für Naturforschung B 56, no. 7 (2001): 571–75. http://dx.doi.org/10.1515/znb-2001-0702.

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Abstract The structures, energies and vibrational frequencies of H2N-NO2 and H2N-NO have been calculated at HF, MP2(FC), MP2(FULL) and CISD levels of theory using a polarized triple-zeta 6-311+G(d,p) basis augmented with a diffuse function. In addition, the structures and energies were also computed at the QCISD(T)/6-311+G(d,p) level of theory. The structure and bonding in H2N-NO2 and H2N-NO is discussed on the basis of a Natural Bond Orbital Analysis (NBO analysis) and in addition based on qualitative valence bond (VB) considerations.

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47

Bavafa, Sadeghali, and Mona Mahboubi. "Investigation of hydrogen bonding between nitrosamine and sulfuric acid using Density Functional Theory." Analele Universitatii "Ovidius" Constanta - Seria Chimie 25, no. 1 (2014): 5–10. http://dx.doi.org/10.2478/auoc-2014-0001.

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Abstract DFT calculations were performed to analyze those interactions; B3LYP and B3PW91 methods were applied and the following basis sets were used: 6-311++G(2d, 2p), 6-311++G(3df, 3pd) and aug-cc-pVDZ. The natural bond orbital (NBO) analysis and atom in molecules (AIM) theory were applied to understand the nature of the interactions. The most stable complex NS1 with an eight-membered cyclic structure contains two O- H· ··O and N-H·· ·O hydrogen bonding interactions. From the values of r(r) at O·· ·H critical points, it can be concluded that the H-boding in eight-membered cyclic NS1 is strong

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Najafi, Meysam, and Syed Ali Raza Naqvi. "Theoretical study of the substituent effect on the hydrogen atom transfer mechanism of the irigenin derivatives antioxidant action." Journal of Theoretical and Computational Chemistry 13, no. 02 (2014): 1450010. http://dx.doi.org/10.1142/s0219633614500102.

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In this paper, 21 substituents with various electron donating and electron withdrawing characters were placed in available positions of irigenin in order to study their effect on the O – H bond dissociation enthalpy (BDE) via DFT/B3LYP method. Results indicated the substituents in X3 and X4 positions have exerted stronger influence upon BDE values of irigenin derivatives when compared with same substituents in X1 and X2 positions. The results show that intramolecular hydrogen bond effects are able to considerably stabilize the parents and radicals. The natural bond orbital (NBO) analysis resul

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Tetteh, Samuel. "Coordination Behavior of Ni2+, Cu2+, and Zn2+ in Tetrahedral 1-Methylimidazole Complexes: A DFT/CSD Study." Bioinorganic Chemistry and Applications 2018 (2018): 1–8. http://dx.doi.org/10.1155/2018/3157969.

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The interaction between nickel (Ni2+), copper (Cu2+), and zinc (Zn2+) ions and 1-methylimidazole has been studied by exploring the geometries of eleven crystal structures in the Cambridge Structural Database (CSD). The coordination behavior of the respective ions was further investigated by means of density functional theory (DFT) methods. The gas-phase complexes were fully optimized using B3LYP/GENECP functionals with 6-31G∗ and LANL2DZ basis sets. The Ni2+ and Cu2+ complexes show distorted tetrahedral geometries around the central ions, with Zn2+ being a perfect tetrahedron. Natural bond orb

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Karakaya, Mustafa, Fatih Ucun, and Ahmet Tokatlı. "Density Functional Theory Study on Conformers of Benzoylcholine Chloride." Journal of Spectroscopy 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/369342.

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The optimized molecular structures and vibrational frequencies and also gauge including atomic orbital (GIAO)1H and13C NMR shift values of benzoylcholine chloride [(2-benzoyloxyethyl) trimethyl ammonium chloride] have been calculated using density functional theory (B3LYP) method with 6-31++G(d) basis set. The comparison of the experimental and calculated infrared (IR), Raman, and nuclear magnetic resonance (NMR) spectra has indicated that the experimental spectra are formed from the superposition of the spectra of two lowest energy conformers of the compound. So, it was concluded that the com

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