Journal articles: 'Moller-Plesset Perturbation'

1

Wolinski, Krzysztof. "Moller-Plesset perturbation theory with two-configurational reference wavefunction." Theoretica Chimica Acta 82, no. 6 (1992): 459–71. http://dx.doi.org/10.1007/bf01129103.

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2

Li, Qingxu, Xianju Zhou, and Shiwei Yin. "Electron Correlation Effects on the Longitudinal Polarizabilities and Second Hyperpolarizabilities of Polyenes: A Finite Field Study." International Journal of Photoenergy 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/346272.

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We carry out ab initio calculations, based on finite-field scheme, of the longitudinal polarizabilities (αL) and second hyperpolarizabilities (γL) of conjugated polyenes, and study the effects of electron correlation, with second-order Moller-Plesset perturbation theory and coupled cluster with singles and doubles method. Calculations with density functional theory are also made to compare with wave-function based methods. Our study shows that electron correlation reduces linear longitudinal polarizability and enhances longitudinal second hyperpolarizability for short polyenes, but the effects decrease as the chain increases; choosing appropriate basis sets is important when quantitative results are required.

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3

Maroulis, G., and A. J. Thakkar. "Static hyperpolarisabilities and polarisabilities for Be: a fourth-order Moller-Plesset perturbation theory calculation." Journal of Physics B: Atomic, Molecular and Optical Physics 21, no. 23 (December 14, 1988): 3819–31. http://dx.doi.org/10.1088/0953-4075/21/23/004.

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4

Remko, Milan. "Ab initio study of the configuration and protonation of thiocarbamic acid." Collection of Czechoslovak Chemical Communications 54, no. 2 (1989): 297–302. http://dx.doi.org/10.1135/cccc19890297.

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The ab initio SCF method was applied to a conformation study of thiocarbamic acid. The 3-21 G calculations revealed that the trans isomer with the O-H···S intramolecular hydrogen bond is more stable than the cis isomer. The calculated rotational barrier for the rotation about the central C-N bond is very high, 125.5 kJ mol-1; this value, however, decreased to 106.2 kJ mol-1 by electron correlation determined at the 2nd order Moller-Plesset perturbation level. Proton affinities for the protonation of the electronegative atoms in the acid increase in the order of the atoms N, O and S. Changes in the Mulliken gross atomic populations are examined in dependence on the configuration and protonation of the acid.

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ZHANG, D. W., and J. Z. H. ZHANG. "FULL AB INITIO COMPUTATION OF PROTEIN-WATER INTERACTION ENERGIES." Journal of Theoretical and Computational Chemistry 03, no. 01 (March 2004): 43–49. http://dx.doi.org/10.1142/s0219633604000891.

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A method to perform full quantum mechanical (ab initio) calculation of interaction energy involving a macromolecule like protein has recently been developed. This new scheme, named molecular fractionation with conjugate caps (MFCC), decomposes a protein molecule into amino acid-based fragments. These individual fragments are properly treated to preserve the chemical property of the bonds that are cut. Through proper combination of interaction energies between the molecule and individual fragments and their conjugate caps, the full protein-molecule interaction energy can be obtained to a high degree-of-accuracy by full ab initio calculations. Here we report a benchmark full ab initio calculation of interaction energy between a HIV-1 gp41 protein (with 982 atoms) and a water molecule at various geometries using HF (Hartree Fock), DFT (density functional theory) and MP2 (second-order Moller-Plesset perturbation theory) methods on a standard workstation.

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Remko, Milan. "Ab initio MO study of protonation of carbamic acid, methyl carbamate and methyl N-methylcarbamate." Collection of Czechoslovak Chemical Communications 53, no. 6 (1988): 1141–48. http://dx.doi.org/10.1135/cccc19881141.

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The ab initio SCF method was applied to the protonation of the carbonyl group in carbamic acid and its methyl derivatives, viz. methyl carbamate and methyl N-methylcarbamate. Complete geometry optimization was accomplished for these compounds and their protonated species using the MINI-1, 3-21 G, and 6-31 G* bases and the proton affinities were calculated at the MINI-1, 3-21 G, 6-31 G*, and 6-31 G** levels. 2nd and 3rd order Moller-Plesset perturbation calculations were also performed for examining the effect of the correlation energy on the calculated protonation energies. The carbonyl protonation energies were found to increase in order carbamic acid < methyl carbamate < methyl N-methylcarbamate. The absolute values of calculated gas phase proton affinities depend on the basis used and way of evaluating the correlation energy. The results are discussed with respect to the theoretical proton affinities of structurally related amides and to related available theoretical gas phase proton affinities.

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7

Liegener, C. M. "Third-order many-body perturbation theory in the Moller-Plesset partitioning applied to an infinite alternating hydrogen chain." Journal of Physics C: Solid State Physics 18, no. 32 (November 20, 1985): 6011–22. http://dx.doi.org/10.1088/0022-3719/18/32/012.

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8

He, Yuan, and Dieter Cremer. "Assessment of higher order correlation effects with the help of Moller-Plesset perturbation theory up to sixth order." Molecular Physics 98, no. 18 (September 2000): 1415–32. http://dx.doi.org/10.1080/002689700417538.

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9

Pople, J. A., M. Head-Gordon, and Krishnan Raghavachari. "Corrections to correlations energies beyond fourth order moller-plesset (MP4) perturbation theory. Contributions of single, double, and triple substitutions." International Journal of Quantum Chemistry 34, S22 (March 12, 1988): 377–82. http://dx.doi.org/10.1002/qua.560340842.

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10

GAO, YI, YU ZHAO, and X. C. ZENG. "REEXAMINATION OF LOW ENERGY STRUCTURES OF ${\rm Au}_{4}^{-}$ AND Au4." Journal of Theoretical and Computational Chemistry 09, supp01 (January 2010): 1–7. http://dx.doi.org/10.1142/s0219633610005499.

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Low energy isomers of [Formula: see text] and Au4 were reexamined using the hybrid density functional B3LYP method and the couple-cluster method with the aug-cc-pVDZ-PP and aug-cc-pVTZ-PP basis sets. For [Formula: see text], the B3LYP method favors the zigzag isomer and the second order Moller–Plesset perturbation (MP2) total energy calculation favors the D2h rhombus isomer, whereas the couple-cluster singles and doubles with perturbative triples [CCSD(T)] level of theory favors the Y-shaped C2v isomer. The pyramid isomer is much higher in energy and could be easily excluded. The Gibbs free energy correction based on harmonic approximation suggests that the zigzag isomer is lower in free energy than the D2h rhombus isomer at 298.15 K. These results confirm that the Y-shaped C2v isomer is the global minimum at both 0 K and room temperature and is thus the major isomer to account for the experimental photoelectron spectrum. The zigzag isomer is suggested, as a minor isomer, to account for the weak second peak at 3.40 eV in the experimental photoelectron spectrum. For neutral Au4 , the zigzag isomer is more stable than D2h rhombus isomer at the B3LYP level and the D2h rhombus isomer is the global minimum on basis of all post Hartree–Fock levels of theory.

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11

Danilov, V. I., and V. M. Anisimov. "The study of the canonical Watson-Crick DNA base pairs by Moller-Plesset perturbation method: the nature of their stability." Biopolymers and Cell 20, no. 1-2 (March 20, 2004): 71–76. http://dx.doi.org/10.7124/bc.000693.

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12

Tan, Xiaojun, Ping Li, Weihua Wang, Gengxiu Zheng, and Qiufen Wang. "A theoretical study of the mechanism of the addition reaction between carbene and azacyclopropane." Journal of the Serbian Chemical Society 75, no. 5 (2010): 649–57. http://dx.doi.org/10.2298/jsc090303031t.

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The mechanism of the addition reaction between carbene and azacyclopropane was investigated using the second-order Moller-Plesset perturbation theory (MP2). By using the 6-311+G* basis set, geometry optimization, vibrational analysis and the energy properties of the involved stationary points on the potential energy surface were calculated. From the surface energy profile, it can be predicted that there are two reaction mechanisms. The first one (1) is carbene attack at the N atom of azacyclopropane to form an intermediate, 1a (IM1a), which is a barrierfree exothermic reaction. Then, IM1a can isomerize to IM1b via a transition state 1a (TS1a), in which the potential barrier is 30.0 kJ/mol. Subsequently, IM1b isomerizes to a product (Pro1) via TS1b with a potential barrier of 39.3 kJ/mol. The other one (2) is carbene attack at the C atom of azacyclopropane, firstly to form IM2 via TS2a, the potential barrier is 35.4 kJ/mol. Then IM2 isomerizes to a product (Pro2) via TS2b with a potential barrier of 35.1 kJ/mol. Correspondingly, the reaction energy for the reaction (1) and (2) is -478.3 and -509.9 kJ/mol, respectively. Additionally, the orbital interactions are also discussed for the leading intermediate.

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13

Azimi, Samira, and Arvi Rauk. "On the Involvement of Copper Binding to the N-Terminus of the Amyloid Beta Peptide of Alzheimer's Disease: A Computational Study on Model Systems." International Journal of Alzheimer's Disease 2011 (2011): 1–15. http://dx.doi.org/10.4061/2011/539762.

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Density functional and second order Moller-Plesset perturbation theoretical methods, coupled with a polarizable continuum model of water, were applied to determine the structures, binding affinities, and reduction potentials of Cu(II) and Cu(I) bound to models of the Asp1, Ala2, His6, and His13His14 regions of the amyloid beta peptide of Alzheimer's disease. The results indicate that the N-terminal Asp binds to Cu(II) together with His6 and either His13 or His14 to form the lower pH Component I of Aβ. Component II of Aβis the complex between Cu(II) and His6, His13, and His14, to which an amide O (of Ala2) is also coordinated. Asp1 does not bind to Cu(II) if three His residues are attached nor to any Cu(I) species to which one or more His residues are bound. The most stable Cu(I) species is one in which Cu(I) bridges the Nδof His13 and His14 in a linear fashion. Cu(I) binds more strongly to Aβthan does Cu(II). The computed reduction potential that closely matches the experimental value for Cu(II)/Aβcorresponds to reduction of Component II (without Ala2) to the Cu(I) complex after endergonic attachment of His6.

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14

Rayne, Sierra, and Kaya Forest. "Benchmarking semiempirical, Hartree–Fock, DFT, and MP2 methods against the ionization energies and electron affinities of short- through long-chain [n]acenes and [n]phenacenes." Canadian Journal of Chemistry 94, no. 3 (March 2016): 251–58. http://dx.doi.org/10.1139/cjc-2015-0526.

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Vertical and adiabatic ionization energies (IEs) and electron affinities (EAs) were calculated for the n = 1–10 [n]acenes using a wide range of semiempirical, Hartree–Fock, density functional, and second-order Moller–Plesset perturbation theory model chemistries. None of the model chemistries examined was able to accurately predict the IEs or EAs for both short- through long-chain [n]acenes, as well as for extrapolations to the polymeric limit, when compared to available experimental and benchmark theoretical data. Except for 6-31G(d), the choice of the basis set does not affect B3LYP results significantly. Analogous calculations using a suite of eight modern and (or) popular density functionals for the n = 1–10 [n]phenacenes revealed similar problems in estimating the IEs and EAs of these compounds, with the sole exception of the M062X functional for adiabatic IEs and potentially the APFD, B3LYP, and MN12SX functionals for adiabatic EAs. The poor IE/EA prediction performance for the parent [n]acenes and [n]phenacenes may extend to their substituted derivatives and heteroatom-substituted analogs. Consequently, caution should be exercised in the application of non-high-level calculations for estimating the IE/EA of these important classes of materials.

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15

SHALABI, A. S., KH M. EID, M. A. KAMEL, and Z. M. FATHI. "M CENTER DIFFUSION, EXCITONS AND ADSORPTIVITY OF ATOMIC H AND He ON LiH (001) SURFACE: ab initio STUDY." International Journal of Modern Physics C 11, no. 08 (December 2000): 1491–507. http://dx.doi.org/10.1142/s0129183100001498.

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An attempt has been made to examine the energetic properties of M center diffusion, excitons near M 2+, M +, M, M - and M 2- centers and adsorptivity of atomic H and He over defect free and defect containing surfaces of LiH using an ab initio embedded cluster method at the Hatrtree–Fock approximation and Moller–Plesset second order perturbation correction. The results confirm the following, (1) the calculated barriers to diffusion of M center in its lowest triplet excited state is always greater than those in its singlet ground state; (2) the triplet M center is not produced directly by optical processes, but, indirectly by thermal diffusion; (3) the exclusive dependence of exciton bands and the nonexclusive dependence of band gaps on the defect charge; (4) surface relaxation is not more important than bulk relaxation; (5) the M center changes the nature of H adsorption from physical adsorption to chemical adsorption; (6) bulk or surface M 2- changes the nature of LiH from an insulator to a semiconductor; (7) as M center is introduced, the HOMO and LUMO levels of the substrate shift to higher energies and band gaps become narrower. This change in the electronic structure makes charge transfer between adsorbate and substrate levels and spin pairing with atomic H more facile.

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16

Wang, Jian, Leif A. Eriksson, Russell J. Boyd, Zheng Shi, and Benny G. Johnson. "Diazasilene (SiNN): a comparative study of electron density distributions derived from Hartree-Fock, second-order Moller-Plesset perturbation theory, and density functional methods." Journal of Physical Chemistry 98, no. 7 (February 1994): 1844–50. http://dx.doi.org/10.1021/j100058a021.

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17

Ghafoor, Sidra, Asim Mansha, Sadia Asim, Muhammad Usman, Ameer Fawad Zahoor, and Hafiz Saqib Ali. "The structural, spectral, frontier molecular orbital and thermodynamic analysis of 2-hydroxy 2-methyl propiophenone by MP2 and B3LYP methods." Journal of Theoretical and Computational Chemistry 19, no. 05 (July 31, 2020): 2050020. http://dx.doi.org/10.1142/s0219633620500200.

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In the present work, we have studied the 2-hydroxy 2-methyl propiophenone (2H2MPP) theoretically as well as experimentally. The optimized molecular structure has been obtained by the density functional theory (DFT), second-order Moller–Plesset perturbation theory (MP2) and Hartree Fock (HF) in the gas phase as well as in different media like ethanol, DMSO and heptane. FT-IR and FT-Raman spectra were computed as well as recorded and fundamental vibrational wavenumbers were assigned. The electronic absorption spectra were calculated by employing the time-dependent density functional theory (TD-DFT) to get the information about excitation energies, oscillator strength and excited state geometries in gas phase and in different solvent media. Chemical activity and chemical stability obtained by HOMO-LUMO studies using a HF/6-31[Formula: see text]G and MP2/6-311[Formula: see text]G calculations. The chemical interpretation of hyperconjugation interactions obtained by the Natural Bond Orbital (NBO) analysis. Moreover, electrostatic potential (ESP) calculations performed to get the visual representation of relative polarity of molecule. Thermodynamic parameters like enthalpy, entropy, heat capacity, and Gibbs free energy computed with varying temperature from 10[Formula: see text]K to 500[Formula: see text]K. The aim of the current investigation is to find out the quantum chemical properties of the title compound which show an active role in the pharmaceutical and printing industries.

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18

Luo, Jun, Xiaofeng Li, Dingding Xiang, Chenglu Zeng, Hongjing Dai, Dawang Wu, and Maoqi Cao. "P … π Bonds in Complexes of C₂H₂ … PH₂X (X = H, F, Cl, Br, I): Quantum Chemical Analysis." Journal of Physics: Conference Series 2553, no. 1 (August 1, 2023): 012069. http://dx.doi.org/10.1088/1742-6596/2553/1/012069.

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Abstract Non-covalent bonds take a strong in numerous chemical and biological phenomena, bringing them to the forefront of research. We studied the structure and interaction properties of C2H2 and PH2X using quantum chemistry following the Moller-Plesset method (MP2). The results showed that C2H2 and PH2X could form a stable complex (C2H2 … PH2X (X= H, F, Cl, Br, I)) of Cs symmetry. The halogen X was far away from the C2H2 molecule, and the P atom was not directly above the center of the C≡C bond. The molecular interaction energy of C2H2 … PH2X varied between -6.3 and -14.5 kJ/mol. This revealed the generation of a long-range weak interaction. Analysis of the interaction energy revealed that the substitution of halogen atoms promoted the formation of the complex (C2H2 … PH2X). The interaction energy of the complex decreased in the order F>Cl>Br>I, which was consistent with the change in electronegativity of the halogen atoms. Independent Gradient Model (IGM) analysis calculations showed that van der Waals interaction was the dominant weak interaction in C2H2 … PH2X. The symmetry-adapted perturbation theory (SAPT) was used to study the system, and the results revealed that the interactions in C2H2 … PH3, C2H2 … PH2I were primarily dispersive, and the interactions in C2H2 … PH2F, C2H2 … PH2Cl, C2H2 … PH2Br were primarily electrostatic.

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19

Novoa, Juan J. "A quantum approach to the mechanism of electrochemical reductions." Canadian Journal of Chemistry 64, no. 12 (December 1, 1986): 2359–64. http://dx.doi.org/10.1139/v86-389.

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Using the Hartree–Fock method and, in some cases, the second order Moller–Plesset perturbational method, with 4-31G, 4-31 + G, and 4-31 + G* basis sets, a first approach to the study of the mechanism of electrochemical reduction from formaldehyde to ethanol is presented. The total energy and optimized geometry of each of the molecules involved are also given. A proton–electron–proton–electron type mechanism is proposed.

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20

"The thermochemistry and reaction pathways of energetic material decomposition and combustion." Philosophical Transactions of the Royal Society of London. Series A: Physical and Engineering Sciences 339, no. 1654 (May 15, 1992): 365–76. http://dx.doi.org/10.1098/rsta.1992.0042.

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The chemical processes involved in the decomposition and combustion of energetic materials have been investigated theoretically using quantum chemical methods to determine the thermochemistry and reaction pathways. The Bond-Additivity-Corrected Moller-Plesset fourth-order perturbation theory method (BAC-MP4) has been used to determine heats of formation and free energies of reaction intermediates of decomposition and combustion. In addition, the BAC-MP4 method has been used to determine reaction pathways involving these intermediates. A theoretical method for calculating solvation energies has been developed to treat the non-idealities of high pressure and the condensed phase. The resulting chemical processes involving decomposition, ignition and combustion are presented for nitramines and nitromethane. Differences in decomposition mechanisms for the condensed phase and gas phase are discussed. In addition, we discuss the effects that amines can have on the initial stages of condensed-phase nitromethane decomposition. Bond dissociation energies for nitro-triazoles are compared with those of other nitro compounds.

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21

SOSA, C., and H. B. SCHLEGEL. "ChemInform Abstract: Calculated Barrier Heights for OH + C2H2 and OH + C2H4 Using Unrestricted Moller-Plesset Perturbation Theory with Spin Annihilation." ChemInform 18, no. 44 (November 3, 1987). http://dx.doi.org/10.1002/chin.198744088.

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22

邱梓恒, Ahmed Yousif Ghazal, 龙金友, and 张嵩. "Theoretical studies on molecular conformers and infrared spectra of Triethylamine." Acta Physica Sinica, 2022, 0. http://dx.doi.org/10.7498/aps.71.20220123.

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Based on the method of density functional theory B3LYP with 6-311++G(d, p) basis set, the potential energy surface of conformational isomerization along the two-dimensional coordinates formed by the dihedral angles ?1(C9N1C2C5) and ?2(C16N1C9C12) within the range -180°~180° were scanned. And 12 ground state conformers of triethylamine were identified. Furthermore, with second-order Moller-Plesset perturbation theory MP2 on the same basis set level, the structures of six lower-energy conformers were optimized and their energies were estimated. The results showed that G1 and G1' with C3 symmetry are the most stable conformers and G4 and G4' with new methyl orientations are identified. In addition, some vibrational modes in the infrared spectra of G1~G4 were assigned and discussed. The infrared spectra of G1~G4 showed that the intensity is weak in the range of 0~1600 cm-1, while the intensity is strong in the range of 2800~3300 cm-1. The characteristic vibration modes such as umbrella vibration and CH stretching vibration were assigned. The average shift of the corresponding infrared peaks on different conformations is estimated to be less than 20 cm-1.

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23

Patil, Vaishali M., Rohan R. Narkhede, Neeraj Masand, Rameshwar S. Cheke, and Krishnan Balasubramanian. "Molecular insights into Resveratrol and its analogs as SARS-CoV-2 (COVID-19) protease inhibitors." Coronaviruses 01 (December 18, 2020). http://dx.doi.org/10.2174/2666796701999201218142828.

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Introduction: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is plaguing the entire world. Amidst the pandemic, research and development efforts are focused on the challenges associated with SARSCoV-2 structure. Material and Methods: The efficient computational methodologies are applied to screen the available FDA-approved drugs/datasets/libraries to identify potent molecule. In the present study, we have carried out ab initio quantum chemical studies including relativistic effects followed by molecular docking with the SARS-CoV-2 protease target by employing a tailor-made library consisting of molecular analogs of Resveratrol, a natural bioflavonoid. Results: The derived docking results were validated with ab initio quantum computations that included both density functional level (DFT) and Moller-Plesset second order perturbation theories (MP2). We find that Resveratrol and its analogs (R8 and R17) bind to the SARS-CoV-2 protease target. In addition to this the computed IR spectrum is found in agreement with the reported experimental spectra for Resveratrol complexes and thus validates the modeling and reliability of proposed geometries. The solvation energies in aqueous phase obtained using enhanced aug-cc-pVTZ basis sets confirm enhancement of bioavailability for Resveratrol through piperine, a natural alkaloid. Conclusion: The potential of the natural bioflavonoid Resveratrol and its analogs to be investigated through in vivo and in vitro SARS-CoV-2 protease models is concluded. Other: The study investigated potential of natural polyphenols as promising anti-viral therapeutics.

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24

Rayne, Sierra, Sierra Rayne, and Kaya Forest. "Semiempirical, Hartree-Fock, density functional, and second order Moller-Plesset perturbation theory methods do not accurately predict ionization energies and electron affinities of short- through long-chain [n]acenes." Nature Precedings, November 8, 2011. http://dx.doi.org/10.1038/npre.2011.6578.

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Rayne, Sierra, and Kaya Forest. "Semiempirical, Hartree-Fock, density functional, and second order Moller-Plesset perturbation theory methods do not accurately predict ionization energies and electron affinities of short- through long-chain [n]acenes." Nature Precedings, November 8, 2011. http://dx.doi.org/10.1038/npre.2011.6578.1.

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Journal articles on the topic 'Moller-Plesset Perturbation'

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