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DFT computations on vibrational spectra: Scaling procedures to improve the wavenumbers
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In this article, the performance of ab initio and density functional theory (DFT) methods in calculating the vibrational wavenumbers in the isolated state was analyzed, and several scaling procedures were described in detail.Abstract:
Abstract The performance of ab initio and density functional theory (DFT) methods in calculating the vibrational wavenumbers in the isolated state was analyzed. To correct the calculated values, several scaling procedures were described in detail. The two linear scaling equation (TLSE) procedure leads to the lowest error and it is recommended for scaling. A comprehensive compendium of the main scale factors and scaling equations available to date for a good accurate prediction of the wavenumbers was also shown. Examples of each case were presented, with special attention to the benzene and uracil molecules and to some of their derivatives. Several DFT methods and basis sets were used. After scaling, the X3LYP/DFT method leads to the lowest error in these molecules. The B3LYP method appears closely in accuracy, and it is also recommended to be used. The accuracy of the results in the solid state was shown and several additional corrections are presented.read more
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Harmonic Vibrational Frequencies: Approximate Global Scaling Factors for TPSS, M06, and M11 functional families using several common basis sets
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Novel oxovanadium and dioxomolybdenum complexes of tridentate ONO-donor Schiff base ligand: Synthesis, characterization, crystal structures, Hirshfeld surface analysis, DFT computational studies and catalytic activity for the selective oxidation of benzylic alcohols
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Diverse coordination of isoniazid hydrazone Schiff base ligand towards iron(III): Synthesis, characterization, SC-XRD, HSA, QTAIM, MEP, NCI, NBO and DFT study
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Synthesis, spectral characterization, SC-XRD, HSA, DFT and catalytic activity of a dioxidomolybdenum complex with aminosalicyl-hydrazone Schiff base ligand: An experimental and theoretical approach
Hadi Kargar,Mehdi Fallah-Mehrjardi,Reza Behjatmanesh-Ardakani,Khurram Shahzad Munawar,Muhammad Ashfaq,Muhammad Tahir +5 more
TL;DR: In this paper, a new dioxidomolybdenum(VI) complex has been successfully prepared by the reaction of an ONO donor Schiff base, derived by condensing 4-amino-2-hydroxybenzohydrazide and 3-methoxysalicylaldehyde, with MoO2(acac)2.
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Synthesis, crystal structure, spectral characterization, theoretical and computational studies of Ni(II), Cu(II) and Zn(II) complexes incorporating Schiff base ligand derived from 4-(diethylamino)salicylaldehyde
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TL;DR: In this paper , three new nickel(II, copper(II), and zinc(II) complexes were synthesized and characterized by treating symmetrical tetradentate Schiff base ligand (H 2 L ) with Ni(OAc) 2 4H 2 O, Cu(O Ac) 2 ·H 2 OD, and Zn(O AC) 2 −2H O O OD salts, respectively.
References
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Density‐functional thermochemistry. III. The role of exact exchange
TL;DR: In this article, a semi-empirical exchange correlation functional with local spin density, gradient, and exact exchange terms was proposed. But this functional performed significantly better than previous functionals with gradient corrections only, and fits experimental atomization energies with an impressively small average absolute deviation of 2.4 kcal/mol.
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Development of the Colle-Salvetti correlation-energy formula into a functional of the electron density
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Accurate and simple analytic representation of the electron-gas correlation energy
John P. Perdew,Yue Wang +1 more
TL;DR: A simple analytic representation of the correlation energy for a uniform electron gas, as a function of density parameter and relative spin polarization \ensuremath{\zeta}, which confirms the practical accuracy of the VWN and PZ representations and eliminates some minor problems.
Journal ArticleDOI
Density-functional approximation for the correlation energy of the inhomogeneous electron gas
TL;DR: Numerical results for atoms, positive ions, and surfaces are close to the exact correlation energies, with major improvements over the original LM approximation for the ions and surfaces.
Book
AB INITIO Molecular Orbital Theory
TL;DR: In this paper, the use of theoretical models as an alternative to experiment in making accurate predictions of chemical phenomena is discussed, and the formulation of theoretical molecular orbital models starting from quantum mechanics is discussed.
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