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Journal articles on the topic 'DFT-HF'

Author: Grafiati

Published: 2 June 2025

Last updated: 31 July 2025

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1

Santra, Golokesh, and Jan M. L. Martin. "Pure and Hybrid SCAN, rSCAN, and r2SCAN: Which One Is Preferred in KS- and HF-DFT Calculations, and How Does D4 Dispersion Correction Affect This Ranking?" Molecules 27, no. 1 (2021): 141. http://dx.doi.org/10.3390/molecules27010141.

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Using the large and chemically diverse GMTKN55 dataset, we have tested the performance of pure and hybrid KS-DFT and HF-DFT functionals constructed from three variants of the SCAN meta-GGA exchange-correlation functional: original SCAN, rSCAN, and r2SCAN. Without any dispersion correction involved, HF-SCANn outperforms the two other HF-DFT functionals. In contrast, among the self-consistent variants, SCANn and r2SCANn offer essentially the same performance at lower percentages of HF-exchange, while at higher percentages, SCANn marginally outperforms r2SCANn and rSCANn. However, with D4 dispers

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2

Masan, Samuel E. P. P., Fitri N. Febriana, Andi H. Zaidan, Ira Puspitasari, and Febdian Rusydi. "Evaluation of the Electronic Structure Resulting from ab-initio Calculations on Simple Molecules Using the Molecular Orbital Theory." Jurnal Penelitian Pendidikan IPA 7, no. 1 (2021): 107. http://dx.doi.org/10.29303/jppipa.v7i1.545.

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Hartree Fock (HF) and Density Functional Theory (DFT) have been commonly used to model chemical problems. This study uses the Molecular Orbital Theory (MOT) to evaluate the electronic structure of five diatomic molecules generated by HF and DFT calculations. The evaluation provides an explanation of how the orbitals of a molecule come to be and how this affects the calculation of the physical quantities of the molecule. The evaluation is obtained after comparing the orbital wave functions calculated by MOT, HF, and DFT. This study found that the nature of the Highest Occupied Molecular Orbital

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3

Apriliyanto, Yusuf Bramastya, and Naufan Nurrosyid. "Comparative Analysis of Electronic Structures Calculations: A Simple Test Case Set for Kohn-Sham Density Functional Theory and Hartree-Fock Methods." Indonesian Journal of Chemical Studies 2, no. 2 (2023): 54–60. http://dx.doi.org/10.55749/ijcs.v2i2.33.

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A comparative analysis on the performance of Kohn-Sham density functional theory (KS-DFT) and Hartree-Fock (HF) methods to obtain reliable energy and electronic properties has been performed in this study using a simple test case. It is crucial to re-emphasize the key differences between these methods to address common conceptual difficulties that occur among freshmen studying basic computational chemistry. The results suggested that the eigenvalue theorem in determining ionization potential could be well implemented in the HF but not in the KS-DFT method. The total energy difference between i

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4

Ridha, Salah M. A., Zahraa Talib Ghaleb, and Abdulhadi Mirdan Ghaleb. "The Computational Investigation of IR and UV-Vis Spectra of 2-isopropyl-5-methyl-1,4-benzoquinone Using DFT and HF Methods." East European Journal of Physics, no. 1 (March 2, 2023): 197–204. http://dx.doi.org/10.26565/2312-4334-2023-1-26.

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A theoretical study on the thymoquinone compound has been performed through two theoretical methods, DFT/B3LYP and HF with 6-31G, 6-31G(d, p) and 6-31++G(d, p) basis sets using Gaussian 09 program. Some theoretical properties, like vibrational and electronic properties especially UV-Vis and FT-IR spectra, of the title compound were analyzed and then compared with available experimental data. The calculated harmonic vibrational frequencies have been scaled with standard scaling factors 0.9 and 0.965 for HF and DFT/B3LYP, respectively and then compared with available experimental FT-IR spectrum.

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5

Avcı, Davut, Adil Başoğlu, and Yusuf Atalay. "Density Functional Theory and ab initio Hartree-Fock Calculations of Molecular Structure and Vibrational Spectra of Anilinium Nitrate." Zeitschrift für Naturforschung A 63, no. 10-11 (2008): 712–20. http://dx.doi.org/10.1515/zna-2008-10-1115.

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The molecular geometry, vibrational frequencies, infrared intensities, Raman scattering activities and several thermodynamic parameters of anilinium nitrate in the ground state have been calculated by both Hartree-Fock (HF) and three density functional theory (DFT) methods (B3LYP, BLYP and B3PW91) using the 6-31G(d) basis set. The results of the optimized molecular structure are presented and compared with the experimental X-ray structure. The optimized geometric bond lengths are described very well by the HF method while bond angles are reproduced more accurately by the DFT methods. Compariso

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6

Bailey, William C. "DFT and HF–DFT calculations of quadrupole coupling constants in molecules." Chemical Physics 252, no. 1-2 (2000): 57–66. http://dx.doi.org/10.1016/s0301-0104(99)00342-0.

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7

Mohandass, P., S. Perumal, S. T. R. Dhanasekaran, P. Padmavathi, and K. K. Mothilal. "Spectroscopic Investigations, Computational Studies and Molecular Properties of Naphthalene Derivatives." Shanlax International Journal of Arts, Science and Humanities 9, S1-May (2022): 47–69. http://dx.doi.org/10.34293/sijash.v9is1-may.5944.

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Theoretical studies have been carried out on bio active molecules such as Naphthalene (npa) and its derivatives naphthalene-2-sulfonic acid (nsa) and 1-nitroso-2-naphthol (nnol) using both Ab initio HF and DFT-B3LYP methods with 6-311++G(d,2p) basis sets. The geometrical parameters, molecular properties and vibrational spectra of nsa, nnol and npa were calculated and analyzed. Geometrical optimizations of the nsa, nnol and npa molecules were done by Density Functional Theory (DFT) using the B3LYP function and Hartree-Fock (HF) level with 6-311++G(d,2p) basis set. The optimized molecular geomet

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8

Pervaiz, Shamiala, M. Usman Saeed, Hazrat Ali, Y. Saeed, Aamir Khan, and Yousef Mohammed Alanazi. "Monolayer CuBr-based gas sensor to detect habitat and industry-relevant molecules with high sensitivity and selectivity: a first-principles study." RSC Advances 15, no. 20 (2025): 16076–87. https://doi.org/10.1039/d4ra06492e.

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The adsorption characteristics of some environmental gas molecules (HF, CO, CO2, SO2, H2S, NH3, NO and NO2) on the surface of a CuBr monolayer have been studied using DFT+U calculations with Grimme scheme DFT-D2.

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9

Djemil, Rayenne, Ouassila Attoui-Yahia та Djameleddine Khatmi. "DFT-ONIOM study of the dopamine–β-CD complex: NBO and AIM analysis". Canadian Journal of Chemistry 93, № 10 (2015): 1115–21. http://dx.doi.org/10.1139/cjc-2014-0481.

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In this work, we conducted a systematic search of the minimum energy of a dopamine–β-cyclodextrin complex via different ONIOM approaches using both mixed (DFT-HF) and nonmixed (DFT-DFT) combinations. Different density functionals were employed: B3LYP, MPW1PW91, M05-2X, M06-2X, and ωB97X-D. Two different basis sets were used on the dopamine–β-cyclodextrin complex; a lower basis set (3-21G*) is used on β-cyclodextrin and a higher basis set (6-31G(d)) is used on dopamine. To fulfill this task, complexation and deformation energies were determined. The relative performance of these functionals was

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10

A. Ibrahim, Ammar, and Mohammed Khahtan Hasan. "Theoretical Calculations of pKa Values for Substituted Carboxylic Acid." NTU Journal of Pure Sciences 1, no. 1 (2021): 19–26. http://dx.doi.org/10.56286/ntujps.v1i1.142.

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Six different methods of determination have been used for studying ten derivatives of carboxylic compounds. Semi-empirical (AM1 and PM3), Hartree Fock (HF/STO-3G and HF/3-21G), and Density Function Theory (DFT/STO-3G and DFT/6-31G) were employed to calculate many physical theoretical parameters. The calculated data were correlated with experimental values of pKa using different regression(enter, stepwise and simple regression). Depending on the Fisher values, (HF/STO-3G) was shown as the best method for predicted of the pKa data compare to the (PM3) method using enter method. While (HF/3-21G)m

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11

Mattsson, Stefan, and Beate Paulus. "A theoretical study on the binding and electrolytic splitting of hydrogen fluoride on Ni(111) and Ni(211)." Physical Chemistry Chemical Physics 22, no. 8 (2020): 4407–15. http://dx.doi.org/10.1039/c9cp06348j.

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Anhydrous hydrogen fluoride (HF) is electrochemically activated on Ni electrodes in the Simons process. We study the electrode/electrolyte interface using DFT methods and find the splitting of HF to be exothermic even at low cell potentials.

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12

Ojha, Tulsi, Susmita Limbu, Prakash Man Shrestha, Suresh Prasad Gupta, and Krishna Bahadur Rai. "Comparative Computational Study on Molecular Structure, Electronic and Vibrational Analysis of Vinyl Bromide based on HF and DFT Approach." Himalayan Journal of Science and Technology 7, no. 1 (2023): 38–49. http://dx.doi.org/10.3126/hijost.v7i1.61128.

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In this study, we have used the Hartree-Fock and Density Functional Theory method of calculation and compared the equilibrium configuration, electronic and vibrational mode of Vinyl Bromide molecule. The molecule is geometrically optimized initially by using 6-31G basis set with B3LYP functional and then bond angles, bond lengths, dihedral angles and IR spectra are compared respectively. Various groups of atoms in Vinyl Bromide molecule by DFT has more accurate bond length, bond angle values rather than by HF computation when comparing with the experimental values. The ground state energies ar

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13

Alkorta, Ibon, and José Elguero. "A theoretical study of perovskites related to CH3NH3PbX3(X = F, Cl, Br, I)." New Journal of Chemistry 42, no. 16 (2018): 13889–98. http://dx.doi.org/10.1039/c8nj01879k.

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MAPIand related perovskites have been studied using a hybrid DFT/HF DFT method with a simplified “corner” model. Bond dissociation energies and<sup>1</sup>H,<sup>13</sup>C,<sup>15</sup>N and<sup>207</sup>Pb absolute shieldings were calculated.

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14

Shakila, G., S. Periandy, and S. Ramalingam. "Molecular Structure and Vibrational Analysis of 1-Bromo-2-Chlorobenzene Using ab initio HF and Density Functional Theory (B3LYP) Calculations." Journal of Atomic, Molecular, and Optical Physics 2011 (August 11, 2011): 1–10. http://dx.doi.org/10.1155/2011/512841.

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The FT-Raman and FT-IR spectra for 1-bromo-2-chlorobenzene (1B2CB) have been recorded in the region 4000–100 cm−1 and compared with the harmonic vibrational frequencies calculated using HF/DFT (B3LYP) method by employing 6-31+G (d, p) and 6-311++G (d, p) basis set with appropriate scale factors. IR intensities and Raman activities are also calculated by HF and DFT (B3LYP) methods. Optimized geometries of the molecule have been interpreted and compared with the reported experimental values of some substituted benzene. The experimental geometrical parameters show satisfactory agreement with the

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15

Akman, Feride, and Nevin Çankaya. "A study of experimental and theoretical analysis of N-cyclohexylmethacrylamide monomer based on DFT and HF computations." Pigment & Resin Technology 45, no. 5 (2016): 301–7. http://dx.doi.org/10.1108/prt-04-2015-0039.

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Purpose This paper aims to synthesise and characterise N-cyclohexylmethacrylamide (NCMA) monomer which contains thermosensitive group. The characterisation of monomer was performed both theoretically and experimentally. Design/methodology/approach The monomer was prepared by reacting cyclohexylamine with methacryloyl chloride in the presence of triethylamine at room temperature. The synthesised monomer was characterised by using not only Density Functional Theory (DFT) and Hartree–Fock (HF) with the Gaussian 09 software but also fourier transform infrared (FT–IR), 1H and 13C nuclear magnetic r

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16

Rai, Krishna Bahadur, Rishi Ram Ghimire, Chandra Dhakal, Kiran Pudasainee, and Bijay Siwakoti. "Structural Equilibrium Configuration of Benzene and Aniline: A First-Principles Study." Journal of Nepal Chemical Society 44, no. 1 (2024): 1–15. http://dx.doi.org/10.3126/jncs.v44i1.62675.

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The present work describes the equilibrium configuration of aromatic compounds like benzene and aniline molecules using the first principle (ab initio) calculation method implemented by the Gaussian 98 programs. The ground state energy for benzene and aniline molecules obtained using the DFT (B3LYP) calculation is lower than that obtained with the HF+MP2 method which, in turn, is lower than that obtained with the HF calculation. The calculated values of bond length, bond angle, and dihedral angle for these molecules with HF, HF+MP2, and DFT (B3LYP) levels of calculation agree with each other w

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17

Sharma, Bandana, Munish Kumar Yadav, and Shweta Prakash. "MOLECULAR STRUCTURE, EXPERIMENTAL AND THEORETICAL (HF, DFT) SPECTRAL ANALYSIS OF 3,4,5- TRIMETHOXYANILINE." RASAYAN Journal of Chemistry 16, no. 02 (2023): 905–20. http://dx.doi.org/10.31788/rjc.2023.1628371.

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Experimental infrared and laser Raman spectra of 3,4,5-trimethoxyaniline were recorded in the first part of our investigation. Theoretically, using Hartree-Fock and density functional theory, structural properties and vibrational frequencies were estimated. The Hartree-Fock level spectral analysis was conducted using the HF/6-31+G(d,p) and HF/6-311++G(d,p) approaches. The B3LYP/6-31+G(d, p) technique was implemented to accomplish the DFT analysis. Comprehensive details of infrared, Raman intensity, scaled frequencies, reduced masses, and force constants are also presented in this paper. The vi

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18

Bashiz, Roghieh Tarlani, Sara Shahriari, Neda Samiei Soofi, et al. "Basis Sets and Nuclear Magnetic Resonance Shielding Effects for Mixing of MWBN and CNTs." Journal of Computational and Theoretical Nanoscience 13, no. 10 (2016): 6440–45. http://dx.doi.org/10.1166/jctn.2016.5583.

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Density functional theory calculations (DFT), as well as hybrid methods (B3LYP) and HF method for MWCNTs have been carried out to study structural stability. The geometry of the MWCNTs have been optimized at DFT and HF methods within CCPTZ-CCPVZ, EPR-II, EPR-II, 6-31G* and 6-31++G** basis sets. According to GIAO method, NMR parameters have been evaluated. The Gaussian quantum chemical package is used for all calculations. The gauge including atomic orbital (GIAO) approach was applied for chemical shielding calculations of (5, 5)@(10, 10), (3, 3)@(7, 7), (4, 4)@(8, 8) DWCNTs.

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19

Meenakshi, R. "Experimental (FT-IR and FT-Raman) and spectroscopic investigations, electronic properties and conformational analysis by PES scan on 2-methoxy-5-nitrophenol and 2-methoxy-4-methylphenol." RSC Advances 6, no. 26 (2016): 21822–31. http://dx.doi.org/10.1039/c6ra00092d.

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20

Cui, Qiang, and Marcus Elstner. "Density functional tight binding: values of semi-empirical methods in an ab initio era." Phys. Chem. Chem. Phys. 16, no. 28 (2014): 14368–77. http://dx.doi.org/10.1039/c4cp00908h.

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21

Bastos, V. A., T. J. da Silva, and M. J. Caldas. "Thiophene–furan oligomers: beyond-DFT study of electronic and optical properties." Electronic Structure 4, no. 1 (2022): 015004. http://dx.doi.org/10.1088/2516-1075/ac5862.

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Abstract Thiophene oligomers are an important class of organic materials for photovoltaic applications, owing to their unique optoelectronic properties. Recently it has been suggested that incorporation of furan units to the thiophene chains, maintaining the chain structure, namely thienylfuran linear oligomers, can bring improvements to the final material. In this work, we present a theoretical study of thiophene, furan and thienylfuran short chains, up to 4 units. Structural and electronic properties were obtained using Hartree–Fock (HF) and density functional theory (DFT) calculations plus

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22

Joshi, Bhawani Datt. "STRUCTURAL, ELECTRONIC AND VIBRATIONAL STUDY OF 4, 6-DICHLORO-5-METHYLPYRIMIDINE: A DFT APPROACH." Journal of Institute of Science and Technology 22, no. 1 (2017): 51–60. http://dx.doi.org/10.3126/jist.v22i1.17740.

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Molecular structure, molecular electrostatic potential (MEP) and theoretical vibrational spectra of 4, 6-dichloro-5-methylpyrimidine (DMP) molecule have been presented in this paper. The vibrational spectra were calculated for monomer, dimer and unit cell DMP molecule using density function theory (DFT) and ab initio Hartree-Fock (HF) (for monomer) method employing 6-311++G (d, p) basis set using Gaussian 09 program. The frequencies obtained by DFT have smaller values than obtained from HF due to the inclusion of electron correlation in the previous one. Electronic absorption calculations are

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23

LEE, JEONG A., and KISEON KIM. "Computing architectures for DFT-based HF-band energy detection." International Journal of Electronics 75, no. 5 (1993): 817–31. http://dx.doi.org/10.1080/00207219308907161.

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24

Karde, Ravindra, and Baliram Lone. "DFT study of Hydrogen storage capacity on Hf doped graphene." IOP Conference Series: Materials Science and Engineering 1291, no. 1 (2023): 012016. http://dx.doi.org/10.1088/1757-899x/1291/1/012016.

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Abstract We explored the molecular hydrogen storage capacity of complex system with Hafnium doped graphene (Gr-Hf) using the Density Functional Theory (DFT) method. We efficiently adsorbed molecular six hydrogens on the Hf doped graphene surface. The quantum chemically calculated adsorption energy is found negatively in the range of - 344.433 Ry to -333.836 Ry this implies as increasing the adsorbed hydrogen molecule on hafnium doped graphene (Gr-Hf) sheet the adsorption energy decreases continuously. The binding energy of after adsorbing second hydrogen molecule too much larger than the next

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25

Kanaki, Elisavet, Giuseppe Sansone, Lorenzo Maschio, and Beate Paulus. "The effect of electron correlation on the adsorption of hydrogen fluoride and water on magnesium fluoride surfaces." Physical Chemistry Chemical Physics 17, no. 28 (2015): 18722–28. http://dx.doi.org/10.1039/c5cp02017d.

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26

Alharbi, F. F., Shahid Mehmood, Zahid Ali, et al. "First principles calculation to investigate the effect of Mn substitution on Cu site in CeCu_3−xMn_xV₄O₁₂ (x = 0, 1, 2 and 3) system." RSC Advances 13, no. 19 (2023): 12973–81. http://dx.doi.org/10.1039/d3ra00263b.

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27

YADAV, SWATANTRA K., HIRDYESH MISHRA, and ASHWANI K. TIWARI. "A DFT study of temperature dependent dissociation mechanism of HF in HF(H2O)7 cluster." Journal of Chemical Sciences 127, no. 10 (2015): 1839–44. http://dx.doi.org/10.1007/s12039-015-0951-6.

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28

Yanai, Takeshi, George I. Fann, Gregory Beylkin, and Robert J. Harrison. "Multiresolution quantum chemistry in multiwavelet bases: excited states from time-dependent Hartree–Fock and density functional theory via linear response." Physical Chemistry Chemical Physics 17, no. 47 (2015): 31405–16. http://dx.doi.org/10.1039/c4cp05821f.

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A fully numerical method for the time-dependent Hartree–Fock and density functional theory (TD-HF/DFT) with the Tamm–Dancoff (TD) approximation is presented in a multiresolution analysis (MRA) approach.

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29

Yang, Po-Yu, Hsing-Yin Chen, Shin-Pon Ju, Chia-Lin Chang, Gao-Shee Leu, and Che-Hsin Lin. "Catalytic polymerization of naphthalene by HF/BF3 super acid: an ab initio density functional theory study." Physical Chemistry Chemical Physics 20, no. 36 (2018): 23311–19. http://dx.doi.org/10.1039/c8cp02777c.

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The detailed reaction mechanism of naphthalene catalytic polymerization by HF/BF<sub>3</sub> has been investigated by DFT calculations and the directionality of the naphthalene-derived mesophase molecule has been explained.

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30

Kumar, Sarvendra, Rajesh Kumar, Jayant Teotia, and M. K. Yadav. "Experimental and Theoretical (ab initio and DFT) Analysis of UV-Vis Spectra, Thermodynamic Functions and Non-linear Optical Properties of 2-Chloro-3,4-Dimethoxybenzaldehyde." JOURNAL OF ADVANCES IN PHYSICS 8, no. 2 (2015): 2122–34. http://dx.doi.org/10.24297/jap.v8i2.1519.

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In the present work, UV- Visible spectra of 2-Chloro-3,4-Dimethoxybenzaldehyde (2,3,4-CDMB) compoundÂ have been carried out experimentally and theoretically. The ultraviolet absorption spectrum of title compound in three solvents (Acetone, Diethyl Ether, CCl4) of different polarity were examined in the range of 200â€“500 nm. The structure of the molecule was optimized and the structural characteristics were determined by HF and DFT (B3LYP) methods with 6-31+G(d,p) and 6-311++G(d,p) as basis sets. The excitation energy, wavelength corresponds to absorption maxima () and oscillator strength (f)

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31

Schwenk, C. F., and B. M. Rode. "Ab initio QM/MM MD simulations of the hydrated Ca2+ ion." Pure and Applied Chemistry 76, no. 1 (2004): 37–47. http://dx.doi.org/10.1351/pac200476010037.

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The comparison of two different combined quantum mechanical (QM)/molecular mechanical (MM) simulations treating the quantum mechanical region at Hartree-Fock (HF) and B3-LYP density functional theory (DFT) level allowed us to determine structural and dynamical properties of the hydrated calcium ion. The structure is discussed in terms of radial distribution functions, coordination number distributions, and various angular distributions and the dynamical properties, as librations and vibrations, reorientational times and mean residence times were evaluated by means of velocity autocorrelation f

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32

Srinivasan, S., and V. Renganayaki. "Computational Studies of Vibration Spectra and Thermodynamic Properties of Metformin Using HF, DFT Methods." Material Science Research India 8, no. 1 (2011): 165–72. http://dx.doi.org/10.13005/msri/080124.

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The molecular vibrations of metformin, one of the important anti-diabetic drugs to treat Non Insulin Dependent Diabetes Mellitus (NIDDM) have been investigated at room temperature by Fourier transform infrared (FTIR) and Fourier transform Raman (FTR) spectroscopies. The solid phase FTIR and FT-Raman spectra of the title compound have been recorded in the regions 4000-400 and 3500-250 cm-1. A satisfactory band assignment has been made on the fundamental modes of vibration. Employing the ab - initio Hatree –Fock (HF) and Density Function Theory (DFT) methods, the theoretical vibrational frequenc

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33

Songül, BOY, KOTAN Gül, and YÜKSEK Haydar. "Gaussian Calculations of 1-(Morpholine-4-yl-methyl)-3-ethyl-4-(4-hydroxybenzyliden amino)-4,5-dihydro-1H-1,2,4-triazol-5-one Molecule." Chemistry Research Journal 3, no. 3 (2018): 186–95. https://doi.org/10.5281/zenodo.13909604.

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1-(Morpholine-4-yl-methyl)-3-ethyl-4-(4-hydroxybenzylidenamino)-4,5-dihydro-1<em>H</em>-1,2,4-triazol-5-one was optimized by using Density Functional Theory (DFT/B3LYP) and Hatree Fock (HF) methods. Then, from this the most stable structure of the molecule, dipole moments, the HOMO-LUMO energy, total energy of the molecule, bond lengths and mulliken charges were calculated with B3LYP/631G (d,p) and HF/631G (d,p) basis sets. <sup>1</sup>H-NMR and <sup>13</sup>C-NMR isotropic shift values were calculated by the method of GIAO using the program package Gaussian G09. Theoretical and experimental v

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34

Amara, Sarah, Noureddine Tchouar, and Salah Belaidi. "Computational Study of some Double Headed Acyclo-C-Nucleosides." International Letters of Chemistry, Physics and Astronomy 61 (November 2015): 1–11. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.61.1.

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In the present paper we have a focus in a study of theoretical characterization of three double headed acyclo-C-nucleosides, which are a recent target of experimental studies. The structural and electronic properties of double headed acyclo-C-nucleosides, 1,4-bis (3-mercapto-1H-1,2,4-triazol-5-yl) butane-1,2,3,4-tetrol, 1,4-bis (4-amino-5-mercapto-4H-1,2,4-triazol-3-yl) butane-1,2,3,4-tetrol and 5,5'-(1,2,3,4-tetrahydroxybutane-1,4-diyl) bis (1,3,4-oxadiazole-2(3H)-thione), have been investigated theoretically by performing semi-empirical molecular orbital, ab initio Hartree-Fock (HF) and Dens

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35

Amara, Sarah, Noureddine Tchouar, and Salah Belaidi. "Computational Study of some Double Headed Acyclo-C-Nucleosides." International Letters of Chemistry, Physics and Astronomy 61 (November 3, 2015): 1–11. http://dx.doi.org/10.56431/p-old94x.

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In the present paper we have a focus in a study of theoretical characterization of three double headed acyclo-C-nucleosides, which are a recent target of experimental studies. The structural and electronic properties of double headed acyclo-C-nucleosides, 1,4-bis (3-mercapto-1H-1,2,4-triazol-5-yl) butane-1,2,3,4-tetrol, 1,4-bis (4-amino-5-mercapto-4H-1,2,4-triazol-3-yl) butane-1,2,3,4-tetrol and 5,5'-(1,2,3,4-tetrahydroxybutane-1,4-diyl) bis (1,3,4-oxadiazole-2(3H)-thione), have been investigated theoretically by performing semi-empirical molecular orbital, ab initio Hartree-Fock (HF) and Dens

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36

Завілопуло, А. М., та Є. Ю. Ремета. "Іонізація молекул фруктози електронним ударом". Reports of the National Academy of Sciences of Ukraine, № 4 (20 серпня 2024): 24–32. http://dx.doi.org/10.15407/dopovidi2024.04.024.

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Масспектрометричним методом досліджено процеси іонізації молекул фруктози при взаємодії з електронами. Вперше експериментально виміряні потенціал іонізації, енергії появи та повний переріз іонізації. Методами Хартрі—Фока (HF) й теорії функціоналу густини (DFT) розраховано енергетичні структури D- та L-форм молекули фруктози. За повними енергіями молекули та її позитивного іону (адіабатичне наближення) та за енергією зв’язку HOMO молекулярної орбіталі (МО) оцінено потенціал іонізації молекули. Розраховано перерізи однократної іонізації молекули за напівкласичним Binary-Encounter-Bethe (BEB) та

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37

Pervaiz, Shamiala, M. Usman Saeed, Sehrish Khan, et al. "Highly sensitive sensing of CO and HF gases by monolayer CuCl." RSC Advances 14, no. 23 (2024): 16284–92. http://dx.doi.org/10.1039/d4ra01519c.

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Using a first-principles approach, the adsorption characteristics of CO and HF on a CuCl monolayer are studied with Grimme-scheme DFT-D2 for accurate description of the long-range (van der Waals) interactions.

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Xu, Xiaowei, Gen Luo, Zhaomin Hou, Paula L. Diaconescu та Yi Luo. "Theoretical insight into the redox-switchable activity of group 4 metal complexes for the ring-opening polymerization of ε-caprolactone". Inorganic Chemistry Frontiers 7, № 4 (2020): 961–71. http://dx.doi.org/10.1039/c9qi01466g.

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DFT calculations indicate that the Lewis acidity of the catalytic metal center M (Ti, Zr, Hf) explains the redox-switchable activity observed for the ring-opening polymerization of ε-caprolactone by ferrocene derived metal complexes.

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Fatema, Kaniz. "Detection of Tetrachlorobutadiene Isomers Using Density Functional Theory Methods." Journal of Modeling and Simulation of Materials 7, no. 1 (2025): 1–17. https://doi.org/10.21467/jmsm.7.1.1-17.

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The study aims to build upon previous research by incorporating Density Functional Theory (DFT), specifically using the B3LYP functional, to improve the computational methodology for analyzing chlorobutadiene (TCBD) compounds. DFT is chosen for its ability to account for electron correlation effects beyond the mean-field approximation, a limitation found in earlier approaches such as the Hartree-Fock (HF) method. By incorporating electron correlation, DFT provides a more accurate description of molecular properties, making it highly suitable for analyzing complex molecular structures like thos

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Yu, Jia, Yu Cao, Hang Song, Xianlong Wang, and Shun Yao. "Calculations of optical rotation: Influence of molecular structure." Journal of the Serbian Chemical Society 77, no. 7 (2012): 887–98. http://dx.doi.org/10.2298/jsc110905207y.

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Ab initio Hartree-Fock (HF) method and Density Functional Theory (DFT) were used to calculate the optical rotation of 26 chiral compounds. The effects of theory and basis sets used for calculation, solvents influence on the geometry and values of calculated optical rotation were all discussed. The polarizable continuum model, included in the calculation, did not improve the accuracy effectively, but it was superior to ?s. Optical rotation of five or sixmembered of cyclic compound has been calculated and 17 pyrrolidine or piperidine derivatives which were calculated by HF and DFT methods gave a

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Hait, Diptarka, Adam Rettig, and Martin Head-Gordon. "Beyond the Coulson–Fischer point: characterizing single excitation CI and TDDFT for excited states in single bond dissociations." Physical Chemistry Chemical Physics 21, no. 39 (2019): 21761–75. http://dx.doi.org/10.1039/c9cp04452c.

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HF/DFT orbitals spin-polarize when single bonds are stretched past the Coulson–Fischer point. We report unphysical features in the excited state potential energy surfaces predicted by CIS/TDDFT in this regime, and characterize their origin.

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Rai, Krishna Bahadur, Nabin Kumar Teemilsina, and Bijay Siwakoti. "First principles study of structural equilibrium configuration of Ortho-, Meta-, and Para-chloroaniline molecules." Scientific World 17, no. 17 (2024): 7–18. http://dx.doi.org/10.3126/sw.v17i17.66414.

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This work has studied the ground state energy, binding energy, equilibrium geometry, charge distribution, and dipole moment of ortho-, meta-, and para-chloroanilines using a wide range of advanced theoretical methods including first-principles Hartree-Fock (HF), Mϕller-Plesset (MP) perturbation theory, Configuration Interaction (CI) and Density Functional Theory [DFT (B3LYP)] with basis sets 3-21G, 4-31G, 6-31G, 6-31G*, 6-31G**, 6-311G, 6-311G*, and 6-311G**. The trend in ground state energy is obtained in EDFT < EHF+MP3 < EHF+MP2 < ECISD < EHF. The calculated binding energies for

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Hernández-Garcı́a, R. M., N. Barba-Behrens, R. Salcedo, and G. Höjer. "Theoretical study of 2-guanidinobenzimidazole. HF, MP2 and DFT calculations." Journal of Molecular Structure: THEOCHEM 637, no. 1-3 (2003): 55–72. http://dx.doi.org/10.1016/s0166-1280(03)00370-1.

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Toumlilin, A., M. Houmad, K. Ribag, Y. Kaddar, A. Benyoussef, and A. El Kenz. "Unveiling the potential of HF and CO molecules adsorption on fluorographene as a gas sensor: DFT insights." Journal of Physics D: Applied Physics 58, no. 15 (2025): 155302. https://doi.org/10.1088/1361-6463/adb981.

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Abstract The adsorption of toxic gases molecules such as HF and CO on functionalized fluorographene is an emerging research frontier. This study pioneers the exploration of HF and CO interactions with fluorographene material, enabling innovative applications such as gases sensors. This paper proposes fluorographene (FG) as a potential candidate for gas sensors in order to prevent the harmful effects of the HF and CO gas molecules. Thus, using quantum espresso, and based on density functional theory (DFT) calculations, we focused on studying the adsorption of HF and CO gas molecules over the fl

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Zavodnik, Valery, Adam Stash, Vladimir Tsirelson, Roelof de Vries, and Dirk Feil. "Electron density study of urea using TDS-corrected X-ray diffraction data: quantitative comparison of experimental and theoretical results." Acta Crystallographica Section B Structural Science 55, no. 1 (1999): 45–54. http://dx.doi.org/10.1107/s0108768198005746.

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The electron-density distribution in urea, CO(NH2)2, was studied by high-precision single-crystal X-ray diffraction analysis at 148 (1) K. An experimental correction for TDS was applied to the X-ray intensities. R merge(F 2) = 0.015. The displacement parameters agree quite well with results from neutron diffraction. The deformation density was obtained by refinement of 145 unique low-order reflections with the Hansen & Coppens [Acta Cryst. (1978), A34, 909–921] multipole model, resulting in R = 0.008, wR = 0.011 and S = 1.09. Orbital calculations were carried out applying different potenti

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Glushkov, A., V. Kovalchuk, A. Sofronkov, and A. Svinarenko. "OPTIMIZED QUASIPARTICLE DENSITY FUNCTIONAL APPROACH FOR MULTIELECTRON ATOMIC SYSTEMS." Photoelectronics, no. 29 (December 28, 2021): 38–44. http://dx.doi.org/10.18524/0235-2435.2020.29.225482.

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We present the optimized version of the quasiparticle density functional theory (DFT), constructed on the principles of the Landau-Migdal Fermi-liquids theory and principles of the optimized one-quasiparticle representation in theory of multielectron systems. The master equations can be naturally obtained on the basis of variational principle, starting from a Lagrangian of an atomic system as a functional of three quasiparticle densities. These densities are similar to the Hartree-Fock (HF) electron density and kinetical energy density correspondingly, however the third density has no an analo

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Gokila, A., and S. Ayyappan. "Quantum chemical insight properties of glyphosine(N, N-Bis (phosphonomethyl) glycine) – a combined hf and density functional study." Digest Journal of Nanomaterials and Biostructures 16, no. 2 (2021): 535–54. http://dx.doi.org/10.15251/djnb.2021.162.535.

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The ab initio HF and Density Functional (DFT / B3LYP) method with a 6-31G(d, p) basis was used to declare a geometric structure and vibrational wave ranges of the glyphosine (GPS) (N, N-Bis (phosphonomethyl) glycine). HF and DFT calculations have optimized geometric hops. The B3LYP method, basis set on a 6-31 G (d, p), is the best level in theory for repeating constructive wave numbers.Density functional theory was used to explore the first hyperpolarizability (β) of the GPS. The results of the computations also indicate that the fragment GPS could be analyzed with Natural Bond Orbital (NBO).

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Анатолий Анатольевич, Крылов,, Алексеев, Владимир Георгиевич, and Феофанова, Мариана Александровна. "COMPUTER SIMULATION OF THE STRUCTURE OF THE DIPHENYLCYCLOHEXADIENEDIIMINE MOLECULE." Вестник Тверского государственного университета. Серия: Химия, no. 4(50) (January 18, 2023): 56–61. http://dx.doi.org/10.26456/vtchem2022.4.7.

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Молекулу N,N-дифенилциклогекса-2,5-диен-1,4-диимина можно рассматривать как структурный фрагмент макромолекулы полианилина в окисленном состоянии. Сравнительный расчѐт структуры этой молекулы проведѐн методами молекулярной механики, полуэмпирической квантовой механики и ab initio (HF и DFT). При расчѐте методом DFT использованы функционалы ωB97X-D3, ωB97M-V, ωPBE-D3, M11, M06HF-D3, BLYP-D3, M05-2X-D3, M06-D3, M06-2X-D3, PW6B95-D3, TPSSh, PBE-D3(BJ), B97-D3(BJ), B3LYP-D3, PBE0-D3, TPSS и базис 6-31G**++. Показано, что все методы хорошо воспроизводят значения длин связей и валентных углов. Однак

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Mondal, Nityagopal, Sannyasi Charan Mandal, and Gourab Kanti Das. "Diastereoselectivity in intramolecular ene cyclisation A theoretical study." Canadian Journal of Chemistry 82, no. 4 (2004): 539–50. http://dx.doi.org/10.1139/v04-002.

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Diastereoselectivity in unactivated and activated ene cyclisation can be predicted using HF/6-31G(d) optimized geometry of the transition states. Relative energies of different conformations of the transition states, calculated using DFT, can be used for the prediction of product ratios. It was found that the dihedral angle around the forming carboncarbon bond controls the cistrans diastereoselectivity. A set of three model pericyclic transition structures has been proposed that mimics the activation process of ene cyclisation.Key words: intramolecular ene reaction, ab initio, DFT.

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Aboulmouhajir, Aziz, SAID Mouatarif, Mohiéeddine Hachim, Naoual El Hamdani, and Mostafa Chhiba. "Theoretical and Spectroscopic investigations of conformations, rotational barriers and scaled vibrations of 2,3-dimethyl hexane." Mediterranean Journal of Chemistry 6, no. 3 (2017): 60–70. http://dx.doi.org/10.13171/mjc61/01701191705/aboulmouhajir.

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The 2,3-dimethyl hexane conformational isomerism has been investigated in detail, based on HF, Post-HF and DFT calculations at different basis set. The effect of size of basis, ZPE, thermal contributions, electronic correlation and optimization methods on the conformational stability was discussed. The rotational barriers from the most stable conformer to the lowest energy secondary conformers and their correspondent inversion barriers at both HF and MP2 methods using 6-31G* basis set have also been approached. A normal mode calculation of the most and less-stable conformers using a scaled ab

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