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Artículos de revistas sobre el tema "Ab initio computations"

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Publicado: 22 de febrero de 2025

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1

Zhang, Zhen, Dong-Bo Zhang, Tao Sun y Renata M. Wentzcovitch. "The Phonon Quasiparticle Approach for Anharmonic Properties of Solids". Journal of Physics: Conference Series 2207, n.º 1 (1 de marzo de 2022): 012042. http://dx.doi.org/10.1088/1742-6596/2207/1/012042.

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Abstract Knowledge of lattice anharmonicity is essential to elucidate distinctive thermal properties in crystalline solids. Yet, accurate ab initio investigations of lattice anharmonicity encounter difficulties owing to the cumbersome computations. Here we introduce the phonon quasiparticle approach and review its application to various materials. This method efficiently and reliably addresses lattice anharmonicity by combining ab initio molecular dynamics and lattice dynamics calculations. Thus, in principle, it accounts for full anharmonic effects and overcomes finite-size effects typical of ab initio molecular dynamics. The validity and effectiveness of the current approach are demonstrated in the computation of thermodynamic and heat transport properties of weakly and strongly anharmonic systems.
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2

Storm, Freja E., Maria Harris Rasmussen, Kurt V. Mikkelsen y Thorsten Hansen. "Computational construction of the electronic Hamiltonian for photoinduced electron transfer and Redfield propagation". Physical Chemistry Chemical Physics 21, n.º 31 (2019): 17366–77. http://dx.doi.org/10.1039/c9cp03297e.

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The construction of open-system diabatic Hamiltonians relevant for the investigation of electron transfer processes is a computational challenge. Here all relevant parameters for Redfield propagations are extracted from ab initio computations.
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3

Clementi, Enrico. "Ab initio computations in atoms and molecules". IBM Journal of Research and Development 44, n.º 1.2 (enero de 2000): 228–45. http://dx.doi.org/10.1147/rd.441.0228.

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4

George, W. O., B. F. Jones, Rh Lewis y J. M. Price. "Ab initio computations on simple carbonyl compounds". Journal of Molecular Structure 550-551 (septiembre de 2000): 281–96. http://dx.doi.org/10.1016/s0022-2860(00)00391-4.

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5

Re, Giuseppe Del y Amedeo Capobianco. "MO-LCAO approach and ab initio computations". International Journal of Quantum Chemistry 106, n.º 9 (2006): 2014–25. http://dx.doi.org/10.1002/qua.20971.

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6

Nacsa, András B. y Gábor Czakó. "Benchmark ab initio proton affinity of glycine". Physical Chemistry Chemical Physics 23, n.º 16 (2021): 9663–71. http://dx.doi.org/10.1039/d1cp00376c.

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7

Jørgensen, Uffe Gråe. "Molecular Data for Stellar Opacities". Highlights of Astronomy 10 (1995): 576–78. http://dx.doi.org/10.1017/s1539299600012107.

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In total, 40 neutral diatomic molecules, 2 molecular ions, and 7 polyatomic molecules are known from observed photospheric stellar spectra. Line data for opacity computations (i.e., lists of line frequencies, intensities, and excitation energies) exist for 17 of these molecules, although the data are complete only for a handful of them. A detailed description of stellar photospheric molecules can be found in Tsuji (1986), and the existing opacity data have been reviewed by Jorgensen (1995).Listed line frequencies in the data bases are either the measured values, or based on computed molecular constants obtained from fits to measured values. Attempts to compute ab initio line frequencies have so far resulted in lower accuracy than what is obtained by use of molecular constants. Published line strengths include measured values as well as ab initio values. For strong bands the ab initio intensities are as accurate as the laboratory values, whereas measured values for weak bands are generally more accurate than the ab initio values. The primary advantage of ab initio computations is therefore that the complete set of all transitions can be obtained. Exploratory studies have shown that completeness of the line data is crucial for the obtained stellar photospheric structure.As an alternative to the ab initio computations of the line intensities, fits to experimental data have been attempted. The most promising method seems to be to fit the dipole function by use of a Padé approximant. Combined with a potential fitted to experimental energy levels, such a dipole function can in principle be used to predict the complete list of band intensities and line intensities for all bands with energies up to the molecular dissociation energy. The part of the dipole function which corresponds to the largest stretching (or bending) of the molecule is the most uncertain in such fits as well as in ab initio computations. This part is responsible for most of the many weak transitions, and large uncertainties are therefore to be excepted in the computed intensities of the weak spectral bands. As these are of major importance for the stellar photospheric structure (due to their huge number and their pseudo continuous appearance in the spectrum), a particularly large effort is desirable in comparing computed intensities with laboratory data for a representative sample of weak bands. Unfortunately, only few measurements of weak bands exist.
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8

König, G. y G. Stollhoff. "Why polyacetylene dimerizes: Results of ab initio computations". Physical Review Letters 65, n.º 10 (septiembre de 1990): 1239–42. http://dx.doi.org/10.1103/physrevlett.65.1239.

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9

Shariatinia, Z., A. Sheykhpour y M. Yousefi. "New Phosphoramidates: Spectroscopic Study and Ab Initio Computations". Phosphorus, Sulfur, and Silicon and the Related Elements 186, n.º 8 (1 de agosto de 2011): 1768–81. http://dx.doi.org/10.1080/10426507.2010.532840.

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10

Bauschlicher, Charles W. y John W. Lawson. "Phenolic polymer–surface interactions from ab initio computations". Molecular Physics 110, n.º 19-20 (10 de mayo de 2012): 2371–80. http://dx.doi.org/10.1080/00268976.2012.683883.

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11

Lee, Sebastian J. R., J. Wayne Mullinax y Henry F. Schaefer. "Intermolecular interactions and proton transfer in the hydrogen halide–superoxide anion complexes". Physical Chemistry Chemical Physics 18, n.º 8 (2016): 6201–8. http://dx.doi.org/10.1039/c5cp05878c.

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12

Halder, Antarip, Sohini Bhattacharya, Ayan Datta, Dhananjay Bhattacharyya y Abhijit Mitra. "The role of N7 protonation of guanine in determining the structure, stability and function of RNA base pairs". Physical Chemistry Chemical Physics 17, n.º 39 (2015): 26249–63. http://dx.doi.org/10.1039/c5cp04894j.

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13

Badri, Ayda, Leonid Shirkov, Nejm-Eddine Jaidane y Majdi Hochlaf. "Explicitly correlated potential energy surface of the CO2–CO van der Waals dimer and applications". Physical Chemistry Chemical Physics 21, n.º 28 (2019): 15871–78. http://dx.doi.org/10.1039/c9cp02657f.

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14

Sarkar, Shubhra, P. K. Sruthi, N. Ramanathan y K. Sundararajan. "Strong proton-shared hydrogen bonding in a methyl imidazole⋯HCl complex: evidence from matrix isolation infrared spectroscopy and ab initio computations". New Journal of Chemistry 44, n.º 17 (2020): 7116–28. http://dx.doi.org/10.1039/d0nj00029a.

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15

Jalife, Said, Judy I.-Chia Wu, Gerardo Martínez-Guajardo, Paul von Ragué Schleyer, María A. Fernández-Herrera y Gabriel Merino. "The 9-homocubyl cation rearrangement revisited". Chemical Communications 51, n.º 25 (2015): 5391–93. http://dx.doi.org/10.1039/c4cc08071h.

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16

Tasi, Domonkos A., Zita Fábián y Gábor Czakó. "Rethinking the X− + CH3Y [X = OH, SH, CN, NH2, PH2; Y = F, Cl, Br, I] SN2 reactions". Physical Chemistry Chemical Physics 21, n.º 15 (2019): 7924–31. http://dx.doi.org/10.1039/c8cp07850e.

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17

Szűcs, Tímea y Gábor Czakó. "Benchmark ab initio stationary-point characterization of the complex potential energy surface of the multi-channel Cl + CH3NH2 reaction". Physical Chemistry Chemical Physics 23, n.º 17 (2021): 10347–56. http://dx.doi.org/10.1039/d0cp06392d.

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18

BAGAYOKO, D. y G. L. ZHAO. "PREDICTIVE AB-INITIO COMPUTATIONS OF PROPERTIES OF FERROELECTRIC MATERIALS". International Journal of Modern Physics B 13, n.º 29n31 (20 de diciembre de 1999): 3767–73. http://dx.doi.org/10.1142/s0217979299003891.

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We present a newly developed, ab-initio, self-consistent procedure for predictive calculations of electronic and related properties of ferroelectric materials. Known as the Bagayoko, Zhao, amd Williams (BZM) procedure, this approach resolves the long-standing disagreement between experimental and theoretical conduction bands, in general, and band gaps, in particular, for ferroelectrical materials and other semiconductors. We discuss applications to tetragonal BaTiO 3 and implications for molecules and band-gap engineering as well as the nuclear shell model.
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19

König, G. y G. Stollhoff. "Why polyacetylene dimerizes — Conclusive results of ab-initio computations". Synthetic Metals 43, n.º 3 (junio de 1991): 3591–96. http://dx.doi.org/10.1016/0379-6779(91)91638-q.

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20

Houk, K. N. "Ab initio and empirical computations of mechanism and stereoselectivity". Pure and Applied Chemistry 61, n.º 4 (1 de enero de 1989): 643–50. http://dx.doi.org/10.1351/pac198961040643.

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21

Avila, Gustavo, Dóra Papp, Gábor Czakó y Edit Mátyus. "Exact quantum dynamics background of dispersion interactions: case study for CH4·Ar in full (12) dimensions". Physical Chemistry Chemical Physics 22, n.º 5 (2020): 2792–802. http://dx.doi.org/10.1039/c9cp04426d.

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22

Ibrahim, Mahmoud A. A., Hassan A. A. Abuelliel, Nayra A. M. Moussa, Al-shimaa S. M. Rady, Shaban R. M. Sayed, Mohamed A. El-Tayeb, Muhammad Naeem Ahmed, Mohamed Khaled Abd El-Rahman y Tamer Shoeib. "σ-Hole, lone-pair-hole, and π-hole site-based interactions in aerogen-comprising complexes: a comparative study". RSC Advances 14, n.º 31 (2024): 22408–17. http://dx.doi.org/10.1039/d4ra03614j.

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23

Kaplan, Dan, Greg Recine y H. Zhang. "An ab-initio study of multiple conformers of glycine". Proceedings of the International Astronomical Union 4, S251 (febrero de 2008): 31–32. http://dx.doi.org/10.1017/s174392130802111x.

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AbstractThe recent combination of new computational chemistry techniques and high performance computational hardware is allowing unprecedented levels of accuracy in the calculations of physical quantities such as potential energy surfaces and rotational-vibrational spectra. Previous results exist in the literature for the first three most stable conformers of glycine at the aug-cc-pVDZ basis set. In this work, we extend the known results, presenting calculations of the four most stable conformers of glycine using the aug-cc-pVQZ basis set. We compare our calculations to experimental values and show that our current calculations differ by <2% from measured values, much better than results from previous years. When searching for molecules in the Interstellar Medium this small difference suggests that computational methods are becoming well-suited for the task. The natural question to ask is: at what point will the small deviation from experimental values render our computations just as reliable as experiments? We feel that the current results show that we are indeed close to this goal.
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24

Ushakov, Sergey V., Alexandra Navrotsky, Qi-Jun Hong y Axel van de Walle. "Carbides and Nitrides of Zirconium and Hafnium". Materials 12, n.º 17 (26 de agosto de 2019): 2728. http://dx.doi.org/10.3390/ma12172728.

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Among transition metal carbides and nitrides, zirconium, and hafnium compounds are the most stable and have the highest melting temperatures. Here we review published data on phases and phase equilibria in Hf-Zr-C-N-O system, from experiment and ab initio computations with focus on rocksalt Zr and Hf carbides and nitrides, their solid solutions and oxygen solubility limits. The systematic experimental studies on phase equilibria and thermodynamics were performed mainly 40–60 years ago, mostly for binary systems of Zr and Hf with C and N. Since then, synthesis of several oxynitrides was reported in the fluorite-derivative type of structures, of orthorhombic and cubic higher nitrides Zr3N4 and Hf3N4. An ever-increasing stream of data is provided by ab initio computations, and one of the testable predictions is that the rocksalt HfC0.75N0.22 phase would have the highest known melting temperature. Experimental data on melting temperatures of hafnium carbonitrides are absent, but minimum in heat capacity and maximum in hardness were reported for Hf(C,N) solid solutions. New methods, such as electrical pulse heating and laser melting, can fill the gaps in experimental data and validate ab initio predictions.
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25

Tasi, Domonkos A., Csenge Tokaji y Gábor Czakó. "A benchmark ab initio study of the complex potential energy surfaces of the OH− + CH3CH2Y [Y = F, Cl, Br, I] reactions". Physical Chemistry Chemical Physics 23, n.º 24 (2021): 13526–34. http://dx.doi.org/10.1039/d1cp01303c.

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26

Mak, Melody L., Salvatore J. Salpietro, R. Daniel Enriz y Imre G. Csizmadia. "An exploratory ab initio study on the conformations of ethylguanidine in its neutral [CH3-CH2-NH-C(=NH)NH2] and protonated [CH3-CH2-NH-C(NH2)2] forms". Canadian Journal of Chemistry 78, n.º 5 (1 de mayo de 2000): 626–41. http://dx.doi.org/10.1139/v00-065.

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To explore the conformation intricacies of the guanidine group in the arginine side chain, ab initio computations have been carried out with ethylguanidine and the ethyl guanidinium ion. HF computations have been performed using 3-21G and 6-31G basis sets and DFT calculations were carried out at the B3LYP/6-31G(d) level of theory. The ethyl guanidinium ion has a single isomer due to its internal symmetry, although this structure has at least three conformations. However, several structures were found and optimized for ethylguanidine, involving the endo- and exo- orientation of the lone NH and torsional angle χ6, as well as the torsional modes associated with χ4 and χ5. Torsional angle χ5 gives rise to s-cis and s-trans structures.Key words: ethylguanidine, ethylguanidinium ion, ab initio MO, arginine side-chain, conformational analysis.
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27

Stoliaroff, Adrien, Jérémy Rio y Camille Latouche. "Accurate computations to simulate the phosphorescence spectra of large transition complexes: simulated colors match experiment". New Journal of Chemistry 43, n.º 30 (2019): 11903–11. http://dx.doi.org/10.1039/c9nj02388g.

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28

Grande-Aztatzi, Rafael, José Luis Cabellos, Rafael Islas, Ivan Infante, José M. Mercero, Albeiro Restrepo y Gabriel Merino. "Planar pentacoordinate carbons in CBe54− derivatives". Physical Chemistry Chemical Physics 17, n.º 6 (2015): 4620–24. http://dx.doi.org/10.1039/c4cp05659k.

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29

Jalife, Said, Sukanta Mondal, Jose Luis Cabellos, Gerardo Martinez-Guajardo, Maria A. Fernandez-Herrera y Gabriel Merino. "The cubyl cation rearrangements". Chemical Communications 52, n.º 16 (2016): 3403–5. http://dx.doi.org/10.1039/c5cc10568d.

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Born–Oppenheimer molecular dynamics simulations and high-level ab initio computations predict that the cage-opening rearrangement of the cubyl cation to the 7H+-pentalenyl cation is feasible in the gas phase.
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30

Chong, Delano P. "Computational study of the anticancer drug cisplatin". Canadian Journal of Chemistry 95, n.º 1 (enero de 2017): 95–104. http://dx.doi.org/10.1139/cjc-2016-0386.

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Systems containing platinum (Pt) are more challenging for reliable computations, because Pt has 78 electrons and requires relativistic treatment. However, to reduce computational demands, most previous researchers used effective core potentials. In this investigation, we perform numerous computations on the cisplatin molecule with ab initio methods and density functional theory, some of which involve all electron and zero-order relativistic approximation. Tentative conclusions on the reliability of various methods are drawn from comparison of our results with previous calculations and available experimental data. Vibrational and electronic spectra are calculated and compared with previous studies and available experimental data.
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31

Jornet-Somoza, J., F. Cosi, M. Fumanal y M. Deumal. "Disentangling the magnetic dimensionality of an alleged magnetically isolated cuprate spin-ladder CuHpCl system: a long-lasting issue". Dalton Transactions 50, n.º 5 (2021): 1754–65. http://dx.doi.org/10.1039/d0dt03499a.

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Ab initio computations reveal that the magnetic topology of CuHpCl is 3D calling into question the validity of being quoted as a spin-ladder system. The calculated magnetization enables discriminating between its gapped, gapless and polarized phases.
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32

Perczel, András, Michael A. McAllister, Pál Császár y Imre G. Csizmadia. "Peptide models. IX. A complete conformational set of For-Ala-Ala-NH2 from ab inito computations". Canadian Journal of Chemistry 72, n.º 10 (1 de octubre de 1994): 2050–70. http://dx.doi.org/10.1139/v94-262.

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This paper reports the complete set of minimum energy (i.e. stable) conformations of For-Ala-Ala-NH2 (containing three peptide bonds), computed by ab initio geometry optimization. A more confident structure and relative energy comparison of the 49 different relaxed geometries was possible using the HF/3-21G method as compared to empirical (force field) methods. The analysis of the different conformers resulted in a useful structure database, incorporating 30 different β-turns, which will have some relevance to the description of peptide folding. Spectroscopic (e.g. NMR) consequences of the reported ab initio calculations are also discussed, and a 3D-structure assignment method for proteins is provided.
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33

TSUZUKI, Seiji y Kazumasa HONDA. "Aspects of High-Level Ab Initio Computations of Intermolecular Interactions". Nihon Kessho Gakkaishi 46, n.º 2 (2004): 165–71. http://dx.doi.org/10.5940/jcrsj.46.165.

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34

Bena Jothy, V., T. Vijayakumar, D. Sajan, V. S. Jayakumar y I. Hubert Joe. "Vibrational spectra and ab initio computations of sarcosinium oxalate monohydrate". Laser Physics 16, n.º 8 (agosto de 2006): 1242–52. http://dx.doi.org/10.1134/s1054660x06080135.

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35

Fang, T. H., M. L. McKee y S. D. Worley. "A theoretical study on the interaction of dinitrogen with rhodium". Canadian Journal of Chemistry 72, n.º 3 (1 de marzo de 1994): 519–22. http://dx.doi.org/10.1139/v94-075.

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Ab initio theoretical computations have been performed for RhN2, Rh+N2, Rh(N2)2, and Rh+(N2)2 species. The computed vibrational frequencies and binding-energy trends are in qualitative accord with prior FTIR studies of N2 interacting with supported Rh films. Computations of the type described herein should be useful in aiding the assignment of observed infrared bands to specific surface species in future work.
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36

Polyansky, Oleg L., Alexander Alijah, Nikolai F. Zobov, Irina I. Mizus, Roman I. Ovsyannikov, Jonathan Tennyson, Lorenzo Lodi, Tamás Szidarovszky y Attila G. Császár. "Spectroscopy of H 3 + based on a new high-accuracy global potential energy surface". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 370, n.º 1978 (13 de noviembre de 2012): 5014–27. http://dx.doi.org/10.1098/rsta.2012.0014.

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The molecular ion is the simplest polyatomic and poly-electronic molecular system, and its spectrum constitutes an important benchmark for which precise answers can be obtained ab initio from the equations of quantum mechanics. Significant progress in the computation of the ro–vibrational spectrum of is discussed. A new, global potential energy surface (PES) based on ab initio points computed with an average accuracy of 0.01 cm −1 relative to the non-relativistic limit has recently been constructed. An analytical representation of these points is provided, exhibiting a standard deviation of 0.097 cm −1 . Problems with earlier fits are discussed. The new PES is used for the computation of transition frequencies. Recently measured lines at visible wavelengths combined with previously determined infrared ro–vibrational data show that an accuracy of the order of 0.1 cm −1 is achieved by these computations. In order to achieve this degree of accuracy, relativistic, adiabatic and non-adiabatic effects must be properly accounted for. The accuracy of these calculations facilitates the reassignment of some measured lines, further reducing the standard deviation between experiment and theory.
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37

Perrella, Fulvio, Federico Coppola, Nadia Rega y Alessio Petrone. "An Expedited Route to Optical and Electronic Properties at Finite Temperature via Unsupervised Learning". Molecules 28, n.º 8 (12 de abril de 2023): 3411. http://dx.doi.org/10.3390/molecules28083411.

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Electronic properties and absorption spectra are the grounds to investigate molecular electronic states and their interactions with the environment. Modeling and computations are required for the molecular understanding and design strategies of photo-active materials and sensors. However, the interpretation of such properties demands expensive computations and dealing with the interplay of electronic excited states with the conformational freedom of the chromophores in complex matrices (i.e., solvents, biomolecules, crystals) at finite temperature. Computational protocols combining time dependent density functional theory and ab initio molecular dynamics (MD) have become very powerful in this field, although they require still a large number of computations for a detailed reproduction of electronic properties, such as band shapes. Besides the ongoing research in more traditional computational chemistry fields, data analysis and machine learning methods have been increasingly employed as complementary approaches for efficient data exploration, prediction and model development, starting from the data resulting from MD simulations and electronic structure calculations. In this work, dataset reduction capabilities by unsupervised clustering techniques applied to MD trajectories are proposed and tested for the ab initio modeling of electronic absorption spectra of two challenging case studies: a non-covalent charge-transfer dimer and a ruthenium complex in solution at room temperature. The K-medoids clustering technique is applied and is proven to be able to reduce by ∼100 times the total cost of excited state calculations on an MD sampling with no loss in the accuracy and it also provides an easier understanding of the representative structures (medoids) to be analyzed on the molecular scale.
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38

Kagomiya, Isao, Keigo Jimbo, Ken-ichi Kakimoto, Masanobu Nakayama y Olivier Masson. "Oxygen vacancy formation and the ion migration mechanism in layered perovskite (Sr,La)3Fe2O7−δ". Phys. Chem. Chem. Phys. 16, n.º 22 (2014): 10875–82. http://dx.doi.org/10.1039/c4cp00736k.

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The characteristic ion migration mechanism for Sr2.46La0.54Fe2O7−δ was investigated by combination of experiments [X-ray diffraction, enthalpy investigations of vacancy formation] and computations [bond valence sum, ab initio density functional theory].
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39

Tsuchiya, Taku, Jun Tsuchiya, Haruhiko Dekura y Sebastian Ritterbex. "Ab Initio Study on the Lower Mantle Minerals". Annual Review of Earth and Planetary Sciences 48, n.º 1 (30 de mayo de 2020): 99–119. http://dx.doi.org/10.1146/annurev-earth-071719-055139.

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Recent progress in theoretical mineral physics based on the ab initio quantum mechanical computation method has been dramatic in conjunction with the rapid advancement of computer technologies. It is now possible to predict stability, elasticity, and transport properties of complex minerals quantitatively with uncertainties that are comparable to or even smaller than those attached in experimental data. These calculations under in situ high-pressure ( P) and high-temperature conditions are of particular interest because they allow us to construct a priori mineralogical models of the deep Earth. In this article, we briefly review recent progress in studying high- P phase relations, elasticity, thermal conductivity, and rheological properties of lower mantle minerals including silicates, oxides, and some hydrous phases. Our analyses indicate that the pyrolitic composition can describe Earth's properties quite well in terms of density and P- and S-wave velocity. Computations also suggest some new hydrous compounds that could persist up to the deepest mantle and that the postperovskite phase boundary is the boundary of not only the mineralogy but also the thermal conductivity. ▪ The ab initio method is a strong tool to investigate physical properties of minerals under high pressure and high temperature. ▪ Calculated thermoelasticity indicates that the pyrolytic composition is representative to the chemistry of Earth's lower mantle. ▪ Simulations predict new dense hydrous phases stable in the whole lower mantle pressure and temperature condition. ▪ Calculated lattice thermal conductivity suggests a heat flow across the core mantle boundary no greater than 10 TW.
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40

Mamedov, Bahtiyar Akber, Ebru Karatas y Elif Somuncu. "Calculation of the Second Virial Coefficient of The TMGa Molecule". International Conference on Applied Engineering and Natural Sciences 1, n.º 1 (20 de julio de 2023): 317–19. http://dx.doi.org/10.59287/icaens.1013.

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In this work, interaction energy values were calculated using ab initio method for Trimethylgallium (TMGa) molecule. For the Trimethylgallium molecules, the minimum energy values obtained by the ab initio method have been used to calculate second virial coefficient by placing in Yukawa potential. The obtained second virial coefficient results are compared to theoretical data reported in the literature. Furthermore, the obtained results for Yukawa potential compared to with other potentials such as Lennard Jones (12-6) potential and Morse potential in the literature. For most of the varied temperatures of the investigated TMGa molecule, the second virial coefficient predicted by theoretical result computations showed reasonable agreement with theoretical second virial coefficient values.
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41

Fokin, Vladimir, Dmitry Minakov y Pavel Levashov. "Ab Initio Calculations of Transport and Optical Properties of Dense Zr Plasma Near Melting". Symmetry 15, n.º 1 (24 de diciembre de 2022): 48. http://dx.doi.org/10.3390/sym15010048.

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The dynamic electrical conductivity of dense Zr plasma near melting is calculated using ab initio molecular dynamics and the Kubo–Greenwood formula. The antisymmetrization of the electronic wave function is considered with the determinant of one-electron wave functions; exchange and correlation effects are treated via an exchange–correlation functional. Optical properties are restored using the Kramers–Kronig transformation. The influence of computational parameters and inner shell electrons on the results is thoroughly investigated. We demonstrate the convergence of our computations and analyze comparison with experimental data.
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42

Park, Buhm Soon. "Between Accuracy and Manageability: Computational Imperatives in Quantum Chemistry". Historical Studies in the Natural Sciences 39, n.º 1 (2009): 32–62. http://dx.doi.org/10.1525/hsns.2009.39.1.32.

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This article explores the place of computation in the history of quantum theory by examining the development of several approximation methods to solve the Schröödinger equation without using empirical information, as these were worked out in the years from 1927 to 1933. These ab initio methods, as they became known, produced the results that helped validate the use of quantum mechanics in many-body atomic and molecular systems, but carrying out the computations became increasingly laborious and difficult as better agreement between theory and experiment was pursued and more complex systems were tackled. I argue that computational work in the early years of quantum chemistry shows an emerging practice of theory that required human labor, technological improvement (computers), and mathematical ingenuity.
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43

Monteiro, Bernardo, Nuno A. G. Bandeira, Célia Lourenço, Ana F. Lucena, José M. Carretas, John K. Gibson y Joaquim Marçalo. "Chemical evidence of the stability of praseodymium(v) in gas-phase oxide nitrate complexes". Chemical Communications 55, n.º 94 (2019): 14139–42. http://dx.doi.org/10.1039/c9cc08006f.

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The diverse gas-phase reactivity of [LnO2(NO3)2]− complexes with water (Ln = Ce, Pr, Nd), examined in a quadrupole ion trap and complemented by ab initio computations, illuminates the chemical stability of Pr in the unusual +5 oxidation state.
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44

Marstokk, K. M., Harald Møllendal, Eero Vänttinen, Tuomas T. Huuhtanen, Martti Dahlqvist, M. M. Kady y S. Brøgger Christensen. "Microwave Spectrum, Conformational Equilibrium and Ab Initio Computations for Ethyl Glycolate." Acta Chemica Scandinavica 46 (1992): 1183–87. http://dx.doi.org/10.3891/acta.chem.scand.46-1183.

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45

Degli Esposti, Alessandra, David G. Lister, Paolo Palmieri y Claudio Degli Esposti. "Ab initio computations of the α vibration–rotation constants for H2O+". Journal of Chemical Physics 87, n.º 11 (diciembre de 1987): 6772–73. http://dx.doi.org/10.1063/1.453419.

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46

Borrelli, Raffaele y Andrea Peluso. "The temperature dependence of radiationless transition rates from ab initio computations". Physical Chemistry Chemical Physics 13, n.º 10 (2011): 4420. http://dx.doi.org/10.1039/c0cp02307h.

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47

Snehalatha, M., C. Ravikumar y I. Hubert Joe. "Spectroscopic investigations and ab initio computations of the dye Chromotrope 2R". Solid State Sciences 11, n.º 7 (julio de 2009): 1275–82. http://dx.doi.org/10.1016/j.solidstatesciences.2009.03.022.

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48

Maiz Hadj Ahmed, H., H. Benaissa, A. Zaoui y M. Ferhat. "Exploring new insights in BAlN from evolutionary algorithms ab initio computations". Physics Letters A 383, n.º 13 (abril de 2019): 1385–88. http://dx.doi.org/10.1016/j.physleta.2019.02.010.

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49

George, William O., Teyfik Has, Md Fokhray Hossain, Bryan F. Jones y Rhobert Lewis. "Hydrogen-bonded forms of ethanol—IR spectra and ab initio computations". Journal of the Chemical Society, Faraday Transactions 94, n.º 18 (1998): 2701–8. http://dx.doi.org/10.1039/a803929a.

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50

Cervellati, R., A. Degli Esposti, D. G. Lister y P. Palmieri. "The conformation of ethyleneurea from microwave spectroscopy and ab initio computations". Journal of Molecular Structure 189, n.º 1-2 (octubre de 1988): 81–88. http://dx.doi.org/10.1016/0022-2860(88)80214-x.

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