Artículos de revistas: "Atomic pair"

1

YONEDA, Yasuhiro. "Atomic Pair Distribution Function (PDF) Analysis of Ferroelectric Materials". Nihon Kessho Gakkaishi 54, n.º 3 (2012): 155–58. http://dx.doi.org/10.5940/jcrsj.54.155.

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2

Volz, Jürgen, Xinxin Hu, Gabriele Maron, Luke Masters, Lucas Pache y Arno Rauschenbeutel. "Single atom photon pair source". EPJ Web of Conferences 266 (2022): 08016. http://dx.doi.org/10.1051/epjconf/202226608016.

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Sources of entangled photon pairs are a crucial ingredient for many applications in quantum information and communication. Of particular interest are narrow-band sources with bandwidths that are compatible with solid state systems such as atomic media for storage and manipulation of the photons. Here, we experimentally realize a source of energy-time entangled photon pairs where the photons pairs are generated by scattering light from a single two-level atom and separated from the coherently scattered light via a narrow-band filter. We verify the performance of our pair-source by measuring the second order correlation function of the atomic fluorescence and we observe that one can continuously tune the photon statistics of the atomic fluorescence from perfect photon anti-bunching to strong photon bunching expected for a photon pair source. Our experiment demonstrates a novel way to realize a photon pair source for photons with spectral bandwidths and resonance frequencies that are inherently compatible with atomic media.

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3

FULDE, P. "COOPER PAIR BREAKING". Modern Physics Letters B 24, n.º 26 (20 de octubre de 2010): 2601–24. http://dx.doi.org/10.1142/s021798491002519x.

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An overview is given of a number of pair-breaking interactions in superconductors. They have in common that they violate a symmetry of the pair state. In most cases pairs are formed from time reversed single-particle states, a noticeable exception being antiferromagnetic superconductors. When time reversibility is broken by an interaction acting on the electrons, the time evolution of the time-reversal operator plays an important role. Depending on whether it is nonergodic or ergodic, we deal with pair weakening or pair breaking. Numerous different interactions are analyzed and discussed. Unifying features of different pair-breaking cases are pointed out. Special attention is paid to the Zeeman effect and to scattering centers with low-energy excitations. The Kondo effect and crystalline field split rare-earth ions belong in that category. Modifications caused by strongly anisotropic pair states are pointed out. There is strong evidence that in some cases intra-atomic excitations lead to pair formation rather than pair breaking for which an explanation is provided.

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4

Shamoto, S., K. Kodama, S. Iikubo y T. Taguchi. "Atomic pair distribution function analysis on nanomaterials". Acta Crystallographica Section A Foundations of Crystallography 64, a1 (23 de agosto de 2008): C73—C74. http://dx.doi.org/10.1107/s0108767308097651.

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5

Rosenberg, Leonard. "Virtual-pair effects in atomic structure theory". Physical Review A 39, n.º 9 (1 de mayo de 1989): 4377–86. http://dx.doi.org/10.1103/physreva.39.4377.

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6

Dzero, M., E. A. Yuzbashyan y B. L. Altshuler. "Cooper pair turbulence in atomic Fermi gases". EPL (Europhysics Letters) 85, n.º 2 (enero de 2009): 20004. http://dx.doi.org/10.1209/0295-5075/85/20004.

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7

Belkacem, Ali y Allan H. Sørensen. "The pair-production channel in atomic processes". Radiation Physics and Chemistry 75, n.º 6 (junio de 2006): 656–95. http://dx.doi.org/10.1016/j.radphyschem.2005.03.003.

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8

Petkov, V. "Atomic-scale structure of nanocrystals by the atomic pair distribution function technique". Molecular Simulation 31, n.º 2-3 (15 de febrero de 2005): 101–5. http://dx.doi.org/10.1080/08927020412331308485.

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9

Vitek, V. "Pair Potentials in Atomistic Computer Simulations". MRS Bulletin 21, n.º 2 (febrero de 1996): 20–23. http://dx.doi.org/10.1557/s088376940004625x.

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Computer modeling of crystal defects ranges at present from generic empirical investigations to first-principle quantum-mechanical calculations (see, for example, References 1–4). Descriptions of atomic interactions in terms of pair potentials dominated such studies until the early 1980s, and many fundamental features of lattice defects and interfaces were revealed in these calculations. The generic results of these studies withstood the test of time, and calculations employing more sophisticated schemes usually confirmed their validity. An early example goes back to the late 1950s when Vineyard and co-workers pioneered the very first computer simulations in their studies of radiation damage. Empirical pair potentials were used in these investigations in which many fundamental, generic aspects of the effect of irradiation of crystalline materials by energetic particles were discovered.Such simple treatments of atomic interactions may appear totally inadequate from the point of view of pure physics. However, it must be recognized that the purpose of the majority of atomistic studies of lattice defects has been to elucidate atomic structure and atomic-level properties in materials with given: (a) crystal structure, (b) elastic properties and possibly phonon spectra, (c) values of certain material parameters such as vacancy formation energies and stacking fault energies, and (d) in alloys, alloying and ordering energies, and possibly antiphase boundary energies. This is in contrast with ab initio studies, the objective of which is to determine all these properties from first principles. These goals of atomistic studies are, of course, the same for all semi-empirical approaches discussed in this collection of articles. In general, the validity of the structural features of lattice defects found in calculations using empirical schemes is best guaranteed if they can be related to fitted material properties and are not sensitively dependent on the deails of the fittings and functional forms employed.

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10

Houbiers, M. y H. T. C. Stoof. "Cooper-pair formation in trapped atomic Fermi gases". Physical Review A 59, n.º 2 (1 de febrero de 1999): 1556–61. http://dx.doi.org/10.1103/physreva.59.1556.

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11

Shamoto, Shin-ichi. "Spherical Nanoparticle Effects on Atomic Pair Distribution Function". Journal of the Physical Society of Japan 79, n.º 3 (15 de marzo de 2010): 034601. http://dx.doi.org/10.1143/jpsj.79.034601.

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12

Billinge, S. J. L. "Nanostructure studied using the atomic pair distribution function". Zeitschrift für Kristallographie 2007, suppl_26 (noviembre de 2007): 17–26. http://dx.doi.org/10.1524/zkri.2007.2007.suppl_26.17.

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13

Oohara, W. y O. Fukumasa. "Hydrogen atomic pair-ion production on catalyst surface". Review of Scientific Instruments 81, n.º 2 (febrero de 2010): 023507. http://dx.doi.org/10.1063/1.3314902.

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14

Billinge, S. J. L. "Nanostructure studied using the atomic pair distribution function". Zeitschrift für Kristallographie Supplements 2007, suppl_26 (noviembre de 2007): 17–26. http://dx.doi.org/10.1524/zksu.2007.2007.suppl_26.17.

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15

Moretti, D., D. Felinto y J. W. R. Tabosa. "Pulse pair generation from coherently prepared atomic ensembles". European Physical Journal D 60, n.º 2 (27 de julio de 2010): 373–82. http://dx.doi.org/10.1140/epjd/e2010-00200-y.

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16

Juhás, P., L. Granlund, S. R. Gujarathi, P. M. Duxbury y S. J. L. Billinge. "Crystal structure solution from experimentally determined atomic pair distribution functions". Journal of Applied Crystallography 43, n.º 3 (30 de abril de 2010): 623–29. http://dx.doi.org/10.1107/s002188981000988x.

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An extension of the Liga algorithm for structure solution from atomic pair distribution functions (PDFs), to handle periodic crystal structures with multiple elements in the unit cell, is described. The procedure is performed in three separate steps. First, pair distances are extracted from the experimental PDF. In the second step the Liga algorithm is used to find unit-cell sites consistent with these pair distances. Finally, the atom species are assigned over the cell sites by minimizing the overlap of their empirical atomic radii. The procedure has been demonstrated on synchrotron X-ray PDF data from 16 test samples. The structure solution was successful for 14 samples, including cases with enlarged supercells. The algorithm success rate and the reasons for the failed cases are discussed, together with enhancements that should improve its convergence and usability.

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17

G, Ariunbold y Gantsog Ts. "Pair - Atomic effect in the micromaser: Narrowing of the linewidth". Физик сэтгүүл 11, n.º 224 (13 de marzo de 2022): 93–101. http://dx.doi.org/10.22353/physics.v11i224.112.

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An average HamiItonian, which contains pair-atomic effects, is used to develop a theory of the micromaser. A modified master equation is derived and both a steady-state and a time-dependent solutions are found showing that, the trapping conditions are disturbed by influence of two atomic events. An approximate as well as an exact spectrum are calculated and narrowing of linewidth is demonstrated within the framework of presented theory.

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18

Shamoto, Shin-ichi, Katsuaki Kodama y Satoshi Iikubo. "Front Line of the Atomic Pair Distribution Function Analysis". hamon 18, n.º 4 (2008): 203–7. http://dx.doi.org/10.5611/hamon.18.203.

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19

Amirav, A. y Mark J. Cardillo. "Electron-Hole Pair Creation by Atomic Scattering at Surfaces". Physical Review Letters 57, n.º 18 (3 de noviembre de 1986): 2299–302. http://dx.doi.org/10.1103/physrevlett.57.2299.

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20

Fry-Petit, Allyson. "Unraveling atomic motions through dynamic pair distribution function analysis". Acta Crystallographica Section A Foundations and Advances 73, a1 (26 de mayo de 2017): a279. http://dx.doi.org/10.1107/s0108767317097252.

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21

Popelier, Paul L. A. y Laurent Joubert. "The Elusive Atomic Rationale for DNA Base Pair Stability". Journal of the American Chemical Society 124, n.º 29 (julio de 2002): 8725–29. http://dx.doi.org/10.1021/ja0125164.

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22

Förster, Arno y Lucas Visscher. "Low-Order Scaling G0W0 by Pair Atomic Density Fitting". Journal of Chemical Theory and Computation 16, n.º 12 (11 de noviembre de 2020): 7381–99. http://dx.doi.org/10.1021/acs.jctc.0c00693.

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23

Ding, J., M. Xu, P. F. Guan, S. W. Deng, Y. Q. Cheng y E. Ma. "Temperature effects on atomic pair distribution functions of melts". Journal of Chemical Physics 140, n.º 6 (14 de febrero de 2014): 064501. http://dx.doi.org/10.1063/1.4864106.

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24

López-Rosa, Sheila, Adrián L. Martín, Juan Antolín y Juan Carlos Angulo. "Electron-pair entropic and complexity measures in atomic systems". International Journal of Quantum Chemistry 119, n.º 7 (5 de diciembre de 2018): e25861. http://dx.doi.org/10.1002/qua.25861.

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25

Abdelmonem, Afaf A., Gamal H. Ragab, Hisham Hashem y Eman A. Bahgat. "Simple Atomic Absorption Spectroscopic and Spectrophotometric Methods for Determination of Pioglitazone Hydrochloride and Carvedilol in Pharmaceutical Dosage Forms". International Journal of Spectroscopy 2014 (18 de mayo de 2014): 1–17. http://dx.doi.org/10.1155/2014/768917.

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This study represents simple atomic absorption spectroscopic and spectrophotometric methods for determination of pioglitazone hydrochloride (PGZ-HCl) and carvedilol (CRV) based on formation of ion-pair associates between drugs and inorganic complex, bismuth(III) tetraiodide (Method A) and between drugs and organic acidic dyes, fast green and orange G (Method B). Method A is based on formation of ion-pair associate between drugs and bismuth(III) tetraiodide in acidic medium to form orange-red ion-pair associates, which can be quantitatively determined by two different procedures. The formed ion-pair associate is extracted by methylene chloride, dissolved in acetone, dried, and then decomposed by hydrochloric acid, and bismuth content is determined by direct atomic absorption spectrometric technique (Procedure 1) or extracted by methylene chloride, dissolved in acetone, and quantified spectrophotometrically at 490 nm (Procedure 2). Method B is based on formation of ion-pair associate between drugs and either fast green dye or orange G dye in acidic medium to form ion-pair associates. The formed ion-pair associate is extracted by methylene chloride and quantified spectrophotometrically at 630 nm (for fast green dye method) or 498 nm (for orange G dye method). Optimal experimental conditions have been studied. Both methods are applied for determination of the drugs in tablets without interference.

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26

Pisipati, V. G. K. M. y Durga Prasad Ojha. "Nematic Behaviour of a Compound EBBA – A Compuational Analysis". Zeitschrift für Naturforschung A 57, n.º 12 (1 de diciembre de 2002): 977–81. http://dx.doi.org/10.1515/zna-2002-1212.

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EBBAA computational analysis has been carried out to determine the configurational preferences of a pair of p-ethoxybenzylidine-p-n-butylaniline () molecules with respect to translatory and orientational motions. The CNDO/2 method has been employed to evaluate the net atomic charge and atomic dipole components at each atomic centre of the molecule. The configurational energy has been computed using the Rayleigh-Schrödinger perturbation method. The interaction energies obtained through these computations were used to calculate the probability of each configuration at 300 K. The energy of a molecular pair during stacking, in-plane, and terminal interaction has been calculated. The results are discussed in the light of other experimental and theoretical results.

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27

Coelho, A. A., P. A. Chater y A. Kern. "Fast synthesis and refinement of the atomic pair distribution function". Journal of Applied Crystallography 48, n.º 3 (22 de mayo de 2015): 869–75. http://dx.doi.org/10.1107/s1600576715007487.

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A fast method for calculating the atomic pair distribution function is described in the context of performing refinements of structural models. Central to the speed of synthesis is the approximation of Gaussian functions of varying full widths at half-maximum using a narrower Gaussian with a fixed full width at half-maximum. The initial Gaussians are first laid down as delta functions which are then convoluted with the narrower Gaussian to form the final pattern. The net result is an algorithm, which has been included in the Rietveld refinement computer programTOPAS, that synthesizes and refines structural parameters a factor of 300–1000 times faster than alternative algorithms/programs, with speed advantages increasing as the number of atomic pairs increases.

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28

Gawai, U. P. y B. N. Dole. "Local structural studies on Co doped ZnS nanowires by synchrotron X-ray atomic pair distribution function and micro-Raman shift". RSC Advances 7, n.º 59 (2017): 37402–11. http://dx.doi.org/10.1039/c7ra02668d.

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The atomic structures of nanowires were studied by X-ray atomic pair distribution function analysis and total synchrotron X-ray scattering data. A PDF method was used to describe a wurtzite and zinc-blended mixed phase model.

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29

Kramer, M. J., R. T. Ott y D. J. Sordelet. "Anisotropic atomic structure in a homogeneously deformed metallic glass". Journal of Materials Research 22, n.º 2 (febrero de 2007): 382–88. http://dx.doi.org/10.1557/jmr.2007.0044.

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The anisotropic atomic structure in a Zr41.2Ti13.8Cu12.5Ni10Be22.5 metallic glass strained during uniaxial tensile creep at 598 K was studied at room temperature using high-energy x-ray diffraction. Changes in the atomic structure were examined by comparing the total scattering function [S(Q)] and the reduced pair distribution function [G(r)] of the creep to that of a companion specimen subjected to the same heat treatment only. Two-dimensional maps of the ΔS(Q) and its Fourier transformation demonstrate the distribution in the bond orientation anisotropy increases with increasing total strain. A fit of the reduced pair distribution function using a simplified two-component model suggests that the bond length changes in the deformed creep samples are not uniform.

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30

Bai, Xiaogang y Haiming Zhang. "Coherent energy transfer of a pair of two-level atoms". Modern Physics Letters B 33, n.º 24 (30 de agosto de 2019): 1950281. http://dx.doi.org/10.1142/s0217984919502816.

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The coherent energy transfer efficiency of a pair of two-level atoms is studied theoretically and its mathematical expression has been deduced. The problem of atoms coherent energy transfer theory is treated by quantum perturbation theory and equivalent method replacing atomic dipole field with light field of the same frequency. The detuning between the donor atom transition frequency and the acceptor atom transition frequency has been studied in the theory. With the increase of the detuning of the two-atomic transition frequency, the energy transfer efficiency decays rapidly. In the case of two-atomic transition frequency resonance, the coherent resonance energy transfer efficiency is directly proportional to the square of the sine of the minus three power of the distance between two atoms and the energy transfer efficiency is periodically decaying over time. The coherent resonance energy transfer efficiency is inversely proportional to the six power of the distance between the two atoms in the first-order approximation.

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31

Mohri, Tetsuo. "Theoretical Investigation of Alloy Phase Equilibria by Continuous Displacement Cluster Variation Method". Solid State Phenomena 172-174 (junio de 2011): 1119–27. http://dx.doi.org/10.4028/www.scientific.net/ssp.172-174.1119.

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Continuous Displacement Cluster Variation Method is employed to study binary phase equilibria on the two dimensional square lattice with Lennard-Jones type pair potentials. It is confirmed that the transition temperature decreases significantly as compared with the one obtained by conventional Cluster Variation Method. This is ascribed to the distribution of atomic pairs in a wide range of atomic distance, which enables the system to attain the lower free energy. The spatial distribution of atomic species around a Bravais lattice point is visualized. Although the average position of an atom is centred at the Bravais lattice point, the maximum pair probability is not necessarily attained for the pairs located at the neighboring Bravais lattice points. In addition to the real space information, k-space information are calculated in the present study. Among them, the diffuse intensity spectra due to short range ordering and atomic displacement are discussed.

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32

Christiansen, Troels Lindahl, Susan R. Cooper y Kirsten M. Ø. Jensen. "There's no place like real-space: elucidating size-dependent atomic structure of nanomaterials using pair distribution function analysis". Nanoscale Advances 2, n.º 6 (2020): 2234–54. http://dx.doi.org/10.1039/d0na00120a.

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33

Du, Zengyi, Hui Li y Kazuhiro Fujita. "Atomic-Scale Visualization of the Cuprate Pair Density Wave State". Journal of the Physical Society of Japan 90, n.º 11 (15 de noviembre de 2021): 111003. http://dx.doi.org/10.7566/jpsj.90.111003.

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34

Tsai, Pin-Ju y Ying-Cheng Chen. "Ultrabright, narrow-band photon-pair source for atomic quantum memories". Quantum Science and Technology 3, n.º 3 (8 de mayo de 2018): 034005. http://dx.doi.org/10.1088/2058-9565/aa86e7.

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35

Skipper, N. T. "Computer Calculation of Water-Clay Interactions Using Atomic Pair Potentials". Clay Minerals 24, n.º 2 (1989): 411–25. http://dx.doi.org/10.1180/claymin.1989.024.2.16.

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36

Yang, Long, Elizabeth A. Culbertson, Nancy K. Thomas, Hung T. Vuong, Emil T. S. Kjær, Kirsten M. Ø. Jensen, Matthew G. Tucker y Simon J. L. Billinge. "A cloud platform for atomic pair distribution function analysis: PDFitc". Acta Crystallographica Section A Foundations and Advances 77, n.º 1 (1 de enero de 2021): 2–6. http://dx.doi.org/10.1107/s2053273320013066.

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A cloud web platform for analysis and interpretation of atomic pair distribution function (PDF) data (PDFitc) is described. The platform is able to host applications for PDF analysis to help researchers study the local and nanoscale structure of nanostructured materials. The applications are designed to be powerful and easy to use and can, and will, be extended over time through community adoption and development. The currently available PDF analysis applications, structureMining, spacegroupMining and similarityMapping, are described. In the first and second the user uploads a single PDF and the application returns a list of best-fit candidate structures, and the most likely space group of the underlying structure, respectively. In the third, the user can upload a set of measured or calculated PDFs and the application returns a matrix of Pearson correlations, allowing assessment of the similarity between different data sets. structureMining is presented here as an example to show the easy-to-use workflow on PDFitc. In the future, as well as using the PDFitc applications for data analysis, it is hoped that the community will contribute their own codes and software to the platform.

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37

Mårtensson-Pendrill, Ann-Marie, Eva Lindroth y Per Öster. "Parity Non-Conservation and Pair Correlation in Heavy Atomic Systems". Physica Scripta T22 (1 de enero de 1988): 300–302. http://dx.doi.org/10.1088/0031-8949/1988/t22/047.

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38

Peterson, Peter F., Emil S. Božin, Thomas Proffen y Simon J. L. Billinge. "Improved measures of quality for the atomic pair distribution function". Journal of Applied Crystallography 36, n.º 1 (21 de enero de 2003): 53–64. http://dx.doi.org/10.1107/s0021889802018708.

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The introduction of neutron spallation-source instruments, such as the General Materials Diffractometer (GEM) at ISIS, allows measurement of pair distribution function (PDF) data at significantly higher rates than previously possible. As a result of the increased rate, a single experiment can produce over a hundred individual runs. Manual processing of all these data using traditional methods becomes inconvenient and inefficient. This article presents quality criteria that help produce automated direct Fourier transformed PDFs of quality similar to hand-processed data, and compares optimization methods.

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39

Petkov, V., Y. Ren, S. Kabekkodu y D. Murphy. "Atomic pair distribution functions analysis of disordered low-Z materials". Physical Chemistry Chemical Physics 15, n.º 22 (2013): 8544. http://dx.doi.org/10.1039/c2cp43378h.

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40

Hoinka, Sascha, Paul Dyke, Marcus G. Lingham, Jami J. Kinnunen, Georg M. Bruun y Chris J. Vale. "Goldstone mode and pair-breaking excitations in atomic Fermi superfluids". Nature Physics 13, n.º 10 (26 de junio de 2017): 943–46. http://dx.doi.org/10.1038/nphys4187.

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41

Granlund, L., S. J. L. Billinge y P. M. Duxbury. "Algorithm for systematic peak extraction from atomic pair distribution functions". Acta Crystallographica Section A Foundations and Advances 71, n.º 4 (29 de mayo de 2015): 392–409. http://dx.doi.org/10.1107/s2053273315005276.

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The study presents an algorithm, ParSCAPE, for model-independent extraction of peak positions and intensities from atomic pair distribution functions (PDFs). It provides a statistically motivated method for determining parsimony of extracted peak models using the information-theoretic Akaike information criterion (AIC) applied to plausible models generated within an iterative framework of clustering and chi-square fitting. All parameters the algorithm uses are in principle known or estimable from experiment, though careful judgment must be applied when estimating the PDF baseline of nanostructured materials. ParSCAPE has been implemented in the Python programSrMise. Algorithm performance is examined on synchrotron X-ray PDFs of 16 bulk crystals and two nanoparticles using AIC-based multimodeling techniques, and particularly the impact of experimental uncertainties on extracted models. It is quite resistant to misidentification of spurious peaks coming from noise and termination effects, even in the absence of a constraining structural model. Structure solution from automatically extracted peaks using the Liga algorithm is demonstrated for 14 crystals and for C60. Special attention is given to the information content of the PDF, theory and practice of the AIC, as well as the algorithm's limitations.

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42

Appel, J. y P. Hertel. "Cooper-pair states for heavy fermions in the atomic representation:UPt3". Physical Review B 35, n.º 1 (1 de enero de 1987): 155–72. http://dx.doi.org/10.1103/physrevb.35.155.

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43

Yang, Yubo, Heng Su, Tianhao Wu, Yuyuan Jiang, Danmin Liu, Pengfei Yan, Haolai Tian y Haijun Yu. "Atomic pair distribution function research on Li2MnO3 electrode structure evolution". Science Bulletin 64, n.º 8 (abril de 2019): 553–61. http://dx.doi.org/10.1016/j.scib.2019.03.019.

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44

Chung, Jean S. y M. F. Thorpe. "Local atomic structure of semiconductor alloys using pair distribution functions". Physical Review B 55, n.º 3 (15 de enero de 1997): 1545–53. http://dx.doi.org/10.1103/physrevb.55.1545.

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45

Jadhav, Ghanshyam. "Spin Atomic Model: Role of Electron Spin in forming Atoms and Molecules". Journal of Physics: Conference Series 2603, n.º 1 (1 de octubre de 2023): 012048. http://dx.doi.org/10.1088/1742-6596/2603/1/012048.

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Abstract This paper recounts the history of atomic models and their limitations in brief. The role of spin motion of paired electrons in building the atoms is a subject of the discussion. The opposite spin velocity of paired electrons in an atom should reduce the repulsion between them. Hence, by adjusting their opposite spin velocity, the force of repulsion between the paired electrons and the force of attraction between the nucleus and the individual electrons in that pair can be balanced without revolving the electrons in orbits. In this way a pair of electrons can maintain their particular distance from the nucleus in atom with adjusting their spin motions. This arrangement easily supports the atoms to build the different molecules, compounds and solid materials. This atomic model may be referred as spin atomic model which should be the fact.

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46

Dmowski, Wojtek y Takeshi Egami. "Observation of structural anisotropy in metallic glasses induced by mechanical deformation". Journal of Materials Research 22, n.º 2 (febrero de 2007): 412–18. http://dx.doi.org/10.1557/jmr.2007.0043.

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We have investigated atomic structure of a Fe81B13Si4C2 metallic glass after mechanical creep deformation. We determined the structure function and pair density function resolved for azimuthal angle using x-ray scattering and a two-dimensional detector. The results are analyzed by the spherical harmonics expansion, and are compared to the often-used simple analysis of the anisotropic pair density function determined by measuring the structure function along two directions with respect to the stress. We observed uniaxial structural anisotropy in a sample deformed during creep experiment. The observed macroscopic shear strain is explained in terms of local bond anisotropy induced by deformation at elevated temperature. The bond anisotropy is a “memory” of this deformation after load was removed. We showed that use of sine-Fourier transformation to anisotropic glass results in systematic errors in the atomic pair distribution function.

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47

Deng, Haiming, Zhi Tan, Chao Kong, Fuqiu Ye y Honghua Zhong. "Pairing Superfluid–Insulator Transition Induced by Atom–Molecule Conversion in Bosonic Mixtures in Optical Lattice". Symmetry 15, n.º 9 (7 de septiembre de 2023): 1715. http://dx.doi.org/10.3390/sym15091715.

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Motivated by the recent experiment on bosonic mixtures of atoms and molecules, we investigate pairing superfluid–insulator (SI) transition for bosonic mixtures of atoms and molecules in a one-dimensional optical lattice, which is described by an extended Bose–Hubbard model with atom–molecule conservation (AMC). It is found that AMC can induce an extra pair–superfluid phase though the system does not demonstrate pair-hopping. In particular, the system may undergo several pairing SI or insulator–superfluid transitions as the detuning from the Feshbach resonance is varied from negative to positive, and the larger positive detuning can bifurcate the pair–superfluid phases into mixed superfluid phases consisting of single-atomic and pair-atomic superfluid. The calculation of the second-order Rényi entropy reveals that the discontinuity in its first-order derivative corresponds to the phase boundary of the pairing SI transition. This means that the residual entanglement in our mean-field treatment can be used to efficiently capture the signature of the pairing SI transition induced by AMC.

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Kaplan, Wayne D. y Giora Kimmel. "Rietveld Analysis and Pair Wise Substitutional Alloys". Advances in X-ray Analysis 35, A (1991): 63–68. http://dx.doi.org/10.1154/s0376030800008673.

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AbstractRietveld Analysis on X-Ray powder diffraction data was used to build a comprehensive model of the structures in gallmm rich R-Ga systems (R is a rare earth between La and Gd). The ability to refine occupation factors as well as atomic positions allowed for the analysis of the e solid solution, its structural relation to the ordered ∊′ phase, and the unique role of the Ga-Ga pairs in these systems.

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49

Ojha, Durga Prasad y V. G. K. M. Pisipati. "Role of Dielectric Medium on a Nematogen. A Statistical Approach Based on Quantum Mechanics and Computer Aided Modelling". Zeitschrift für Naturforschung A 57, n.º 8 (1 de agosto de 2002): 645–49. http://dx.doi.org/10.1515/zna-2002-0802.

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ECCPA statistical analysis has been carried out to determine the configurational preferences of a pair of 5-(4-ethylcyclohexyl)-2-(4-cyanophenyl) pyrimidine () molecules. The CNDO/2 method has been employed to evaluate the net atomic charge and atomic dipole components at each atomic centre of the molecule. The configurational energy has been computed using the Rayleigh-Schrödinger perturbation theory. The total interaction energies obtained by these computations were used to calculate the probability of each configuration in vacuum and in a dielectric medium (benzene) at the phase transition temperature using the Maxwell-Boltzmann formula. On the basis of stacking, in-plane and terminal interaction energy calculations, all possible geometrical arrangements of the molecular pair have been considered. An attempt has been made to explain the nematogenic behavior of liquid crystals and thereby develop a molecular model for liquid crystallinity.

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50

Nakamura, Nathan, Maxwell W. Terban, Simon J. L. Billinge y B. Reeja-Jayan. "Unlocking the structure of mixed amorphous-crystalline ceramic oxide films synthesized under low temperature electromagnetic excitation". Journal of Materials Chemistry A 5, n.º 35 (2017): 18434–41. http://dx.doi.org/10.1039/c7ta06339c.

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