Self-diffusion in gold single crystals at low temperatures

1968 ◽  
Vol 46 (23) ◽  
pp. 2589-2594 ◽  
Author(s):  
J. L. Whitton ◽  
G. V. Kidson
Keyword(s):  
Single Crystals ◽  
Diffusion Coefficients ◽  
Low Temperatures ◽  
Bulk Diffusion ◽  
Lattice Diffusion ◽  
Fast Diffusion ◽  
Initial Portion ◽  
Self Diffusion ◽  
Normal Lattice ◽  
Structure Sensitive

Self-diffusion in gold single crystals has been studied at temperatures between 335 to 390 °C for times between 15 and 30 min. The concentration profiles, obtained by use of a sensitive sectioning technique, consist of a region that appears to be characteristic of bulk diffusion, followed by a deeply penetrating 'tail' that is structure sensitive. Diffusion coefficients extracted from the initial portion of the curves are somewhat larger than those predicted from an extrapolation of high temperature measurements. The results are interpreted in terms of a combination of normal lattice diffusion and fast diffusion along dislocations.

Intermetallic Growth: Structure-Sensitive Effects

2010 ◽  
Vol 297-301 ◽  
pp. 567-572 ◽  
Author(s):  
Lyudmila N. Paritskaya ◽  
Yuri S. Kaganovsky ◽  
V.V. Bogdanov
Keyword(s):  
Diffusion Coefficients ◽  
Coarse Grained ◽  
Fast Diffusion ◽  
Phase Layer ◽  
Free Surfaces ◽  
Self Diffusion ◽  
Intermetallic Growth ◽  
Structure Sensitive ◽  
Simultaneous Existence ◽  
Diffusion Paths

The kinetics of intermetallic growth in the bulk, along the surface and grain boundaries (GBs) was studied in the Cd-Ni, Cd-Cu and Cu-Sn systems. Bulk dynamic diffusion coefficients exceed by a few orders of magnitudes the tracer self-diffusion coefficients in homogeneous phases. The reasons for this difference are discussed in terms of departure of growing intermetallics from stoichiometry due to the simultaneous existence of two processes: interdiffusion through the growing phase layer and chemical reactions at interfaces. Accelerating contribution of GBs and free surfaces, as fast diffusion paths, into diffusion penetrability of growing intermetallics has been investigated. It was found that the rates of lateral phase spreading along free surfaces and GBs exceed several times the rate of phase growth in the bulk. Accelerating GB contribution depends on the grain size. Nano-dispersed thin films demonstrate maximal phase propagation rates, which several times exceed even the rates of lateral phase spreading along free surfaces in coarse-grained polycrystals.

Bulk Diffusion of Homovalent Atomic Probes of Vanadium and Niobium in Single Crystals of Tungsten

2012 ◽  
Vol 330 ◽  
pp. 1-10 ◽  
Author(s):  
S.M. Klotsman ◽  
G.N. Tatarinova ◽  
Alexander N. Timofeev
Keyword(s):  
Single Crystals ◽  
Diffusion Coefficients ◽  
Secondary Ion Mass Spectrometry ◽  
Volume Diffusion ◽  
Bulk Diffusion ◽  
Self Diffusion ◽  
Arrhenius Dependence ◽  
The Difference ◽  
Defect Interactions ◽  
Secondary Ion

The Volume Diffusion of Homovalent Atomic Probes (APs) from the VB Group of the Periodic Ta-Ble of Elements (PTE) – V and Nb in W Single Crystals Has Been Studied by Using the Method of Secondary Ion Mass Spectrometry (SIMS). the Parameters of the Arrhenius Dependence of the Coefficients DV of Vanadium Volume Diffusion in W Have Been Measured: (D0)V = (1.3  0.4) X 10-4 M2s-1 and QV = (564 ± 6) Kj/mol. the Parameters (D0,Q)Nb of the Bulk Diffusion of Nb Aps in W Have Been Estimated with the Help of Several Measured Coefficients Dnb and the Empirical Correlation [1,2]: (D = DWW)(Tm)W: the Diffusion Coefficients of Substitutional Non-Magnetic 5d-Aps Coincide with the Self-Diffusion Coefficients in W at its Melting Point (Tm)W. the Enthalpies Qnb,Ta of the Bulk Diffusion of Non-Magnetic (nm) Homovalent Aps from the VB Group of PTE – Nb and Ta [3] Also Coincide with the Relaxation Volumes vacVBAPs of Complexes “vacancies-VB Aps” in the W Lattice. Electron Contributions (EDN)vacVBAPs to the Energies Evacvbaps of Interaction of Point Defects in Complexes “vacancies- VB Nm- Aps” Are Lower than in Complexes “vacancies-IVB Nm- Aps” [4]. the Dependence of {EDN(n)}vacVBAPs the Electron Contributions (EDN)vacVBAPs on the Difference of N Numbers of Periods of PTE the Deviation of Contributions (EDN)vacVAPs for Vanadium Aps to En-Ergies Evacvaps of their Interaction in Complexes “vacancy-VAP” Has Been Determined. this Devi-Ation Is Conditioned by the Contribution of the Exchange Energy (Eexch)VAP of Vanadium to the En-Ergy Evacvaps of the Point-Defect Interactions in the Complex “vacancy-VAP”.

Bulk Diffusion of Homovalent Non-Magnetic Atomic Probes of Titanium and Zirconium in Tungsten Single Crystals

2011 ◽  
Vol 319-320 ◽  
pp. 1-11 ◽  
Author(s):  
S.M. Klotsman ◽  
G.N. Tatarinova ◽  
Alexander N. Timofeev
Keyword(s):  
Single Crystals ◽  
Point Defects ◽  
Diffusion Coefficients ◽  
Periodic Table ◽  
Secondary Ion Mass Spectrometry ◽  
Volume Diffusion ◽  
Bulk Diffusion ◽  
The Self ◽  
Self Diffusion ◽  
Secondary Ion

The bulk diffusion of homovalent non-magnetic atomic probes (APs) from the IVB group of the periodic table of elements (PTE) – Ti and Zr in tungsten single crystals was investigated by sec-tioning, using secondary ion mass spectrometry (SIMS). The Arrhenius dependences had the fol-lowing parameters: DWTi - (D0)WTi = (3.00.4 ) x 10-4 m2s-1, enthalpy QWTi = (576 ± 9) kJ/mole; DWZr - (D0)WZr = (2.3  0.6) x 10-4 m2s-1, QWZr = (561 9) kJ/mole. The measured parameters (D0,Q)WTi,Zr of diffusion of Ti and Zr atomic probes (APs) in W are in accord with the empirical correlation: the diffusion coefficients of the substitutional APs coincide with the self-diffusion coefficients in W at (Tm)W – its melting temperature. Enthalpies QWTi,Zr,Hf of the volume diffusion of homovalent non-magnetic APs of the IVB group of periodic table of elements (PTE) - Ti, Zr and Hf increase with the decrease of relaxation volumes of the complexes «vacancy-IVBAP» in W lattice. The energies (E)WvacIVBAP of elastic relaxation of the complexes «vacancy-IVBAP» in W lattice were estimated. Electron contributions EDN to the energies EWvacIVBAP of interaction of the point defects in complexes «vacancy-IVBAP» increase relative to value EWvacIIIBAP of interac-tion of the point defects in complexes «vacancy-IIIBAP» with the growth of d-electrons number in comparison with the complexes «vacancy-IIIBAP».

Dislocation-enhanced diffusion in silver single crystals

1970 ◽  
Vol 48 (13) ◽  
pp. 1548-1552 ◽  
Author(s):  
C. T. Lai ◽  
H. M. Morrison
Keyword(s):  
Crystal Lattice ◽  
Single Crystals ◽  
Diffusion Coefficients ◽  
Enhanced Diffusion ◽  
Temperature Range ◽  
Self Diffusion

An electrolytic sectioning technique has been used to measure self-diffusion coefficients in silver single crystals in the temperature range 300–800 °C. The results are analyzed in terms of diffusion through the crystal lattice, enhanced by diffusion along dislocations.

p, T-Dependence of Self Diffusion in Mixtures of Hexane/Ethanol and Hexane/Dimethylether

1995 ◽  
Vol 50 (2-3) ◽  
pp. 149-154 ◽  
Author(s):  
A. Heinrich-Schramm ◽  
W. E. Price ◽  
H.-D. Lüdemann
Keyword(s):  
Hydrogen Bonding ◽  
Qualitative Analysis ◽  
Pressure Dependence ◽  
Diffusion Coefficients ◽  
Low Temperatures ◽  
The Self ◽  
Slight Effect ◽  
Self Diffusion ◽  
Dipole Interactions ◽  
Significant Difference

Abstract Self-diffusion in ethanol/hexane and dimethylether/hexane mixtures of various compositions has been measured at 215-350 K and up to 200 MPa. Qualitative analysis of the results indicates that, as expected, hydrogen bonding retards the self-diffusion of ethanol in the mixture, especially at the low temperatures. Dimethylether shows a slight effect of dipole-dipole interactions on the self-diffu­sion, as seen by a higher ΔE* value than for the alkane. However there is no significant difference in the pressure dependence for both mixtures. This is shown by considering the ratio of the two diffusion coefficients, which suggests that, contrary to what is observed for pure alcohols, pressure has little effect upon the hydrogen bonding of ethanol in the mixture. In additon, there is surprisingly little concentration dependence on the ratios for either mixture.

scholarly journals Li self-diffusion in lithium niobate single crystals at low temperatures

2012 ◽  
Vol 14 (7) ◽  
pp. 2427 ◽  
Author(s):  
J. Rahn ◽  
E. Hüger ◽  
L. Dörrer ◽  
B. Ruprecht ◽  
P. Heitjans ◽  
...  
Keyword(s):  
Lithium Niobate ◽  
Single Crystals ◽  
Low Temperatures ◽  
Self Diffusion

Self-Diffusion in Tin Crystals

1950 ◽  
Vol 3 (1) ◽  
pp. 91 ◽  
Author(s):  
PJ Fensham
Keyword(s):  
Single Crystals ◽  
Diffusion Coefficients ◽  
Vacancy Mechanism ◽  
Self Diffusion ◽  
Active Isotope

The rate of self-diffusion in single crystals of white tin of various orientations has been measured using the radio-active isotope Sn113. The ratio of the diffusion coefficients parallel and perpendicular to the tetragonal (c) axis is approximately 2 at 180 �C. and approximately 3 at 223 �C. The diffusion coefficients in both directions at various temperatures are given by the Arrhenius expressions Dc= 1.2 x 10-5e-10,1500/RT cm.2sec.-1 and Da=3.7 X 10-8e-5,900/RT cm.2sec.-l. The anisotropy is discussed in terms of the vacancy mechanism of diffusion.

First Study of Iron Self-Diffusion in Fe2O3 Single Crystals by SIMS

2005 ◽  
Vol 237-240 ◽  
pp. 277-281 ◽  
Author(s):  
Antônio Claret Soares Sabioni ◽  
Antônio Márcio J.M. Daniel ◽  
W.A.A. Macedo ◽  
M.D. Martins ◽  
Anne Marie Huntz ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Stable Isotope ◽  
Single Crystals ◽  
Diffusion Coefficients ◽  
Secondary Ion Mass Spectrometry ◽  
Depth Profiling ◽  
Reliable Data ◽  
Oxygen Atmosphere ◽  
Self Diffusion ◽  
Secondary Ion

Iron bulk self-diffusion coefficients were measured in Fe2O3 single crystals using an original methodology based on the utilization of 57Fe stable isotope as iron tracer and depth profiling by secondary ion mass spectrometry (SIMS). The iron self-diffusion coefficients measured along c-axis direction, between 900 and 1100o C, in oxygen atmosphere, can be described by the following Arrhenius relationship: D(cm2/s)= 5.2x106 exp [-510 (kJ/mol)/RT], and are similar to reliable data available in the literature, obtained by means of radioactive techniques.

Diffusion coefficients of nitric oxide in water: A molecular dynamics study

2016 ◽  
Vol 30 (27) ◽  
pp. 1650205 ◽  
Author(s):  
Sunil Pokharel ◽  
Nurapati Pantha ◽  
N. P. Adhikari
Keyword(s):  
Nitric Oxide ◽  
Molecular Dynamics ◽  
Mole Fraction ◽  
Diffusion Coefficients ◽  
Low Temperatures ◽  
Mean Square Displacement ◽  
Mutual Diffusion ◽  
Arrhenius Behavior ◽  
Self Diffusion ◽  
Experimental Values

Self-diffusion coefficients along with the mutual diffusion coefficients of nitric oxide (NO) and SPC/E water (H2O) as solute and solvent of the mixture, have been studied within the framework of classical molecular dynamics level of calculations using GROMACS package. The radial distribution function (RDF) of the constituent compounds are calculated to study solute–solute, solute–solvent and solvent–solvent molecular interactions as a function of temperature. A dilute solution of five NO molecules (mole fraction 0.018) and 280 H2O molecules (mole fraction 0.982) has been taken as the sample. The self-diffusion coefficient of the solvent is calculated by using mean square displacement (MSD) where as that for solute (NO) is calculated by using MSD and velocity auto-correlation function (VACF). The results are then compared with the available experimental values. The results from the present work for water come in good agreement, very precise at low temperatures, with the experimental values. The diffusion coefficients of NO, on the other hands, agree well with the available theoretical studies, and also with experiment at low temperatures (up to 310 K). The results at the higher temperatures (up to 333 K), however, deviate significantly with the experimental observations. Also, the mutual diffusion coefficients of NO in water have been calculated by using Darken’s relation. The temperature dependence of the calculated diffusion coefficients follow the Arrhenius behavior.

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