Thermal Transport in Dilute Alloys

1960 ◽  
Vol 13 (2) ◽  
pp. 255 ◽  
Author(s):  
GK White
Keyword(s):  
Point Defects ◽  
Thermal Transport ◽  
Theoretical Data ◽  
Thermal Resistivity ◽  
Lattice Vibrations ◽  
Dilute Alloys ◽  
Lattice Waves ◽  
Experimental Values ◽  
Anharmonic Coupling ◽  
Germanium Silicon

Experimental values of the thermal resistivity for a number of elements, including copper, silver, gold, argon, germanium, silicon, antimony, and bismuth, are compared with theoretical values deduced from the anharmonic coupling between lattice vibrations. For copper-, silver-, and gold�rich alloys experimental and theoretical data for scattering of lattice waves by point defects are compared.

SOME SCATTERING PROBLEMS IN CONDUCTION THEORY

1957 ◽  
Vol 35 (4) ◽  
pp. 441-450 ◽  
Author(s):  
P. G. Klemens
Keyword(s):  
Lattice Thermal Conductivity ◽  
Stacking Faults ◽  
Low Frequency ◽  
Thermal Resistivity ◽  
Lattice Vibrations ◽  
Scattering Problems ◽  
Strain Fields ◽  
Inhomogeneous Strain ◽  
Lattice Waves ◽  
Conduction Theory

An expression is derived for the scattering of electrons by inhomogeneous strain fields in terms of the scattering of electrons by low frequency lattice vibrations, as deduced from the low temperature intrinsic thermal resistivity and the lattice thermal conductivity. This is applied to the scattering of electrons by dislocations and stacking faults. An expression for the scattering of lattice waves by stacking faults is also derived. The validity of these results is discussed.

Thermal Resistivity of Point Defects

1958 ◽  
Vol 110 (2) ◽  
pp. 585-586 ◽  
Author(s):  
Arnold M. Toxen
Keyword(s):  
Point Defects ◽  
Thermal Resistivity

Experimental and Theoretical Studies of 2- (naphthalen-1-yl (piperidin-1-yl) methyl)phenol Compound

2020 ◽  
Vol 42 (6) ◽  
pp. 818-818
Author(s):  
Yeliz Ula Yeliz Ula
Keyword(s):  
Molecular Orbital ◽  
Theoretical Data ◽  
Biologically Active ◽  
Oscillator Strengths ◽  
Excitation Energies ◽  
Petasis Reaction ◽  
Vis Spectroscopy ◽  
Phenol Compound ◽  
Lowest Unoccupied Molecular Orbital ◽  
Experimental Values

The 2- (naphthalen-1-yl (piperidin-1-yl) methyl) phenol compound is an alkylaminophenol compound and has been experimentally synthesized by the Petasis reaction. In this study Structural analysis was carried out by FT-IR, NMR, UV-Vis spectroscopy. The high antioxidant value of the compound showed that it could be a potential biologically active drug. Theoretical data support all experimental analysis of the new compound. Comparisons were made by double method. For this purpose, DFT (B3LYP) and HF methods have been used with 6-311G ++ (d, p) set. Also, the compoundand#39;s electronic and structural properties (bond lengths, bond angles and dihedral angles), the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energies, electrostatic potential (MEP), vibrational frequencies, Mulliken atomic charges, excitation energies, and oscillator strengths were calculated. As a result; the theoretical and experimental values were found to be compatible.

scholarly journals Model Pseudopotentials and Dynamical Properties of Simple Metals

1975 ◽  
Vol 28 (4) ◽  
pp. 403 ◽  
Author(s):  
SK Srivastava
Keyword(s):  
Constant Volume ◽  
Dynamical Model ◽  
Thermal Resistivity ◽  
Dynamical Structure ◽  
Structure Factors ◽  
Dynamical Properties ◽  
Experimental Values

The pseudopotential investigation of the dynamical properties of simple metals is discussed, and various model pseudopotentials are used to determine the thermal resistivity as a function of temperature at constant volume for the b.c.c. metals Li, Na, K, Rb, and Cs and the f.c.c. metals Cu, Ag, and Au. Krebs's (1965) lattice dynamical model is used to supply dynamical structure factors. The resulting theoretical thermal esistivities are compared with available experimental values.

ATOMIC DISPLACEMENTS DUE TO POINT DEFECTS IN Ni DILUTE ALLOYS

2003 ◽  
Vol 17 (12) ◽  
pp. 2417-2428 ◽  
Author(s):  
HITESH SHARMA ◽  
S. PRAKASH
Keyword(s):  
Point Defects ◽  
Strain Field ◽  
Static Method ◽  
Embedded Atom Method ◽  
Relaxation Energy ◽  
Dilute Alloys ◽  
Metal Impurities ◽  
Embedded Atom ◽  
Atomic Displacements ◽  
Transition Metal Impurities

The Embedded atom method has been used to investigate the strain field due to substitutional transition metal impurities in Ni. The calculations are carried out in the discrete lattice model of the metal using Kanzaki lattice static method. The results for atomic displacements due to 3d, 4d and 5d impurities (Cu, Pd, Pt and Au) in Ni are given up to 20 NN's of impurity and are compared with the earlier calculations and with the available experimental data. The maximum displacements of 3.6% of 1NN distance are found for NiAu, while the minimum displacements of 0.78% of 1NN distance are found for NiCu alloy respectively. The relaxation energy for Cu are found less than those for Pd, Au and Pt impurities in the Ni host.

Anharmonic Phonon Interactions at Interfaces and Contributions to Thermal Boundary Conductance

2011 ◽  
Vol 133 (6) ◽  
Author(s):  
Patrick E. Hopkins ◽  
John C. Duda ◽  
Pamela M. Norris
Keyword(s):  
Inelastic Scattering ◽  
Thermal Transport ◽  
Phonon Scattering ◽  
Transmission Model ◽  
Material Interfaces ◽  
Physical Consideration ◽  
New Model ◽  
Thermal Boundary Conductance ◽  
Anharmonic Coupling ◽  
Scattering Events

Continued reduction in characteristic dimensions in nanosystems has given rise to increasing importance of material interfaces on the overall system performance. With regard to thermal transport, this increases the need for a better fundamental understanding of the processes affecting interfacial thermal transport, as characterized by the thermal boundary conductance. When thermal boundary conductance is driven by phononic scattering events, accurate predictions of interfacial transport must account for anharmonic phononic coupling as this affects the thermal transmission. In this paper, a new model for phononic thermal boundary conductance is developed that takes into account anharmonic coupling, or inelastic scattering events, at the interface between two materials. Previous models for thermal boundary conductance are first reviewed, including the diffuse mismatch model, which only considers elastic phonon scattering events, and earlier attempts to account for inelastic phonon scattering, namely, the maximum transmission model and the higher harmonic inelastic model. A new model is derived, the anharmonic inelastic model, which provides a more physical consideration of the effects of inelastic scattering on thermal boundary conductance. This is accomplished by considering specific ranges of phonon frequency interactions and phonon number density conservation. Thus, this model considers the contributions of anharmonic, inelastically scattered phonons to thermal boundary conductance. This new anharmonic inelastic model shows improved agreement between the thermal boundary conductance predictions and experimental data at the Pb/diamond and Au/diamond interfaces due to its ability to account for the temperature dependent changing phonon population in diamond, which can couple anharmonically with multiple phonons in Pb and Au. We conclude by discussing phonon scattering selection rules at interfaces and the probability of occurrence of these higher order anharmonic interfacial phonon processes quantified in this work.

Electron-density-based calculations of intermolecular energy: case of urea

1999 ◽  
Vol 55 (5) ◽  
pp. 821-827 ◽  
Author(s):  
Kyrill Yu. Suponitsky ◽  
Vladimir G. Tsirelson ◽  
Dirk Feil
Keyword(s):  
Interaction Energy ◽  
Electron Density ◽  
Theoretical Data ◽  
Multipole Moments ◽  
Intermolecular Interaction Energy ◽  
Hartree Fock ◽  
Intermolecular Energy ◽  
Crystalline Urea ◽  
To Come ◽  
Experimental Values

The intermolecular interaction energy in crystalline urea has been calculated both from diffraction data and from the Hartree–Fock crystalline electron-density distribution, using a modified atom–atom approximation scheme. The electrostatic part of this energy has been calculated from the atomic multipole moments, obtained by adjustment of the multipole model to experimental X-ray and to theoretical Hartree–Fock structure amplitudes. To obtain the induction energy, multipole moments were calculated from structure amplitudes for the crystalline electron density and from those that refer to the electron density of a superposition of isolated molecules. This worked well for the calculation of the interaction energy from Hartree–Fock data (6% difference from the sublimation-energy value), but not for the interaction energy from experimental data, where the moments of the superposition have to come from Hartree–Fock calculations: the two sets of multipole moments are far too different. The uncertainty of the phases of the structure amplitudes, combined with systematic errors in the theoretical data and noise in the experimental values, may account for the discrepancies. The nature of the different contributions to intermolecular interactions for urea is examined.

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