Results 21 to 30 of about 35,127 (280)
Molecules, 2021 Anharmonic quantum chemical calculations were employed to simulate and interpret a near-infrared (NIR) spectrum of caffeine. First and second overtones, as well as binary and ternary combination bands, were obtained, accurately reproducing the lineshape ...
Justyna Grabska +3 more
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Anharmonic Frequency Analysis [PDF]
Mathematics of Computation, 1972 A new numerical method of frequency analysis is described, designed mainly to search for discrete frequencies in a time series. An integral transform is applied twice to the data for different reference times. A complex amplitude within a selected narrow frequency band is obtained for each transform.
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Quantum Lattice Solitons [PDF]
, 1994 The number state method is used to study soliton bands for three anharmonic quantum lattices: i) The discrete nonlinear Schr\"{o}dinger equation, ii) The Ablowitz-Ladik system, and iii) A fermionic polaron model. Each of these systems is assumed to have $
A.C. Scott +31 more
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Metallicity in a Holstein-Hubbard Chain at Half Filling with Gaussian Anharmonicity
Scientific Reports, 2017 The Holstein-Hubbard model with Gaussian phonon anharmonicity is studied in one-dimension at half filling using a variational method based on a series of canonical transformations.
Ch. Uma Lavanya +2 more
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Molecules, 2021 The vibrational NH stretching transitions in secondary amines with intramolecular NH···O hydrogen bonds were investigated by experimental and theoretical methods, considering a large number of compounds and covering a wide range of stretching wavenumbers.
Poul Erik Hansen +3 more
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Carrier concentration dependence of structural disorder in thermoelectric Sn1−xTe
IUCrJ, 2016 SnTe is a promising thermoelectric and topological insulator material. Here, the presumably simple rock salt crystal structure of SnTe is studied comprehensively by means of high-resolution synchrotron single-crystal and powder X-ray diffraction from 20 ...
Mattia Sist +7 more
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Anharmonic Effects in Ordered Kesterite-Type Cu2ZnSnS4
Solids, 2021 We performed an in-depth investigation and analysis of the effect of temperature on the Raman-active A-modes of bulk kesterite-type Cu2ZnSnS4 within the 300–460 K temperature range. We acquired the individual contributions to each Raman mode, namely, the
Nicole Suss +3 more
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The Role of Vibrational Anharmonicity in the Computational Study of Thermal Spin Crossover
Magnetochemistry, 2019 Spin crossover in transition metal complexes can be studied in great detail with computational chemistry. Over the years, the understanding has grown that the relative stability of high-spin (HS) versus low-spin (LS) states is a subtle balance of many ...
Jianfang Wu, Carmen Sousa, Coen de Graaf
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Thoretical Investigation of Absorptive Oxygen Bonding With Ni(111) Surface [PDF]
شیمی کاربردی روز, 2011 In this work, adsorption of O on Ni(111) surface with p(2Ã2) configuration and coverage value of 0.25 ML is investigated using Density Functional Theory (DFT).
Amir Naser Shamkhali +1 more
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Anharmonicity measure for materials [PDF]
Physical Review Materials, 2020 Theoretical frameworks used to qualitatively and quantitatively describe nuclear dynamics in solids are often based on the harmonic approximation. However, this approximation is known to become inaccurate or to break down completely in many modern functional materials. Interestingly, there is no reliable measure to quantify anharmonicity so far.
Knoop, Florian +3 more
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