A combined MD–ONIOM2 approach for 1H NMR chemical shift calculations including a polar solvent

The effect of both solvent polarity and hydrogen bonding (HB) on the electronic transition energy of Coumarin 102 (C102) has been examined using the time-dependent density functional theory (TDDFT). Solvent effect on both geometry and electronic transition energy is evaluated using the polarizable continuum model (PCM). A linear relation of the absorption maximum of C102 with the solvent polarity function Δf is found using the TDDFT-PCM method for all solvents except dimethyl sulfoxide. The solvent polarity and the type B HB between the carbonyl oxygen and solvent hydrogen atom make the absorption wavelength redshift, whereas the type A HB between the amino nitrogen atom and solvent hydrogen atom has an opposite effect on the absorption wavelength. The calculated absorption wavelengths of C102 with two type B HB between the carbonyl oxygen and solvent hydrogen atom are in excellent agreement with experimental measurements. The solvatochromism of C102 is analyzed in terms of the Kamlet-Taft equation and the parameters s and a are discussed.

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“…At last to give more reliable result, further investigations should be carried out using a combined MD-ONIOM2 approach. 70 …”

Section: Absorption Spectra Of C102 With Several Hb S In Various Solvmentioning

confidence: 99%

Time‐dependent density functional theory study on the absorption spectrum of Coumarin 102 and its hydrogen‐bonded complexes

Zhao

Xia

2010

J Comput Chem

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“…The solute 0166-1280/$ -see front matter Ó 2010 Elsevier B.V. All rights reserved. doi:10.1016/j.theochem.2009.12.038 molecule model was placed in a box of DMSO molecules [1] for the MD run and a radial distribution function (RDF) was used to determine the average distribution of DMSO-oxygen atoms around the acidic protons. The RDF was used to determine the discrete models ( Fig.…”

Section: Methodsmentioning

confidence: 99%

“…The use of the Molecular Dynamics-Our own N-layered Integrated molecular Orbital and Molecular mechanics, with N = 2, (MD-ONIOM2) method for the prediction of 1 H NMR chemical shifts has been previous reported for nevirapine in DMSO [1], with good results when compared to an experimentally measured spectrum. This included the acidic proton that forms a hydrogen bond with a polar DMSO solvent molecule and suffers significant deshielding as a result.…”

Section: Introductionmentioning

confidence: 99%

1H NMR chemical shifts of some DMSO-solvated amines using MD-ONIOM2

Vailikhit

Holzschuh

Hannongbua

2010

Journal of Molecular Structure: THEOCHEM

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“…This problem is known and discussed in the literature, and has recently been described for dimethyl sulfoxide (DMSO). 47 Further, 13 C and 1 H chemical shifts are calculated by the B3LYP/ 6-311++G(2d,2p) method in DMSO. The corresponding results are also listed in Table 3.…”

Section: And 1 H Nmr Studiesmentioning

confidence: 99%

The spectroscopic NMR analysis of 2-dicyanovinyl-5-phenylthiophene by the density functional method

LiXiao-Hong

ZhangXian-Zhou

2013

Can. J. Chem.

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Quantum chemistry calculations have been performed by using the Gaussian03 program to compute the optimized geometry and harmonic vibrational frequency of 2-dicyanovinyl-5-phenylthiophene (C 14 H 8 N 2 S) in the ground state. Atomic charges at B3LYP/6-311++G(d,p) level are also calculated. Potential energy distributions (PEDs) using MOLVIB program are also used to interpret the theoretical vibrational spectra of the title compound. A detailed interpretation of the infrared spectra of the title compound is reported. The theoretical spectrograms for the IR spectra of the title compound have been constructed. The crystal structure obtained by molecular mechanics belongs to the P2 1 space group, with lattice parameters Z = 2, a = 6.6745 Å, b = 14.7672 Å, c = 11.0986 Å, = 0.921 g cm -3 . In addition, the 13 C and 1 H NMR are further investigated by the B3LYP/6-311++G(d,p) and B3LYP/6-311++G(2d,2p) methods. Résumé :On a procédé à des calculs de chimie quantique à l'aide du programme Gaussian03 pour déterminer les fréquences de vibration harmoniques pour une géométrie optimisée du 2-dicyanovinyl-5-phénylthiophène (C 14 H 8 N 2 S) à l'état fondamental. On a également calculé les charges atomiques au niveau B3LYP/6-311++G(d,p). Les distributions des énergies potentielles (PED) obtenues à l'aide du programme MOLVIB sont aussi utilisées pour interpréter les spectres vibrationnels théoriques du composé susmentionné. On présente une interprétation détaillée des spectres infrarouges de ce composé. On a construit les spectrogrammes théoriques de ces spectres infrarouges. La structure cristalline obtenue par la mécanique moléculaire appartient au groupe d'espace P2 1 ayant les paramètres de réseau Z = 2, a = 6,6745 Å, b = 14,7672 Å, c = 11,0986 Å, = 0,921 g cm -3 . En outre, on a étudié la RMN du 13 C et du 1 H par les méthodes B3LYP/6-311++G(d,p) et B3LYP/6-311++G(2d,2p). [Traduit par la Rédaction] Mots-clés : 2-dicyanovinyl-5-phénylthiophène, spectre vibrationnel, DFT, analyse RMN, charges de Mulliken.

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A combined MD–ONIOM2 approach for 1H NMR chemical shift calculations including a polar solvent

Cited by 16 publications

References 18 publications

Time‐dependent density functional theory study on the absorption spectrum of Coumarin 102 and its hydrogen‐bonded complexes

Time‐dependent density functional theory study on the absorption spectrum of Coumarin 102 and its hydrogen‐bonded complexes

1H NMR chemical shifts of some DMSO-solvated amines using MD-ONIOM2

The spectroscopic NMR analysis of 2-dicyanovinyl-5-phenylthiophene by the density functional method

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