A theoretical study of the structure and dynamics of amorphous Fe

The extended theory of transition-metal potential, which includes the transition-metal d states, is used to obtain the effective interatomic interactions in terms of pair potential for amorphous Fe. Pair potential for amorphous Fe is also computed using a simple approach for liquid metals given by de-Angelis and March. We employ the so obtained pair potentials to calculate the longitudinal- and transverse-phonon eigenfrequencies using the theory of phonons in amorphous solids. The results for the phonon eigenfrequencies obtained from these potentials are in good qualitative agreement with the molecular-dynamics results as well as with the theoretical results of Bhatia and Singh. Computation of the Debye temperature and the isothermal bulk modulus also shows a close agreement with other results.

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The Theoretical Study of Electron Dispersion of Some Liquid Metals Using Transition Metal Model Potential (TMMP)

Journal of Nano- and Electronic Physics ◽

10.21272/jnep.10(4).04011 ◽

2018 ◽

Vol 10 (4) ◽

pp. 04011-1-04011-4

Author(s):

Kamaldeep G. Bhatia ◽

◽

N. K. Bhatt ◽

P. R. Vyas ◽

V. B. Gohel ◽

...

Keyword(s):

Transition Metal ◽

Theoretical Study ◽

Liquid Metals ◽

Model Potential ◽

Electron Dispersion

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On the Fluctuation Model of Diffusion in Liquid Metals

Zeitschrift für Naturforschung A ◽

10.1515/zna-1968-0604 ◽

1968 ◽

Vol 23 (6) ◽

pp. 805-813 ◽

Cited By ~ 8

Author(s):

R. A. Swalin

Keyword(s):

Temperature Dependence ◽

Liquid Metals ◽

Pair Potential ◽

Constant Volume ◽

Liquid Sodium ◽

Pair Potentials ◽

Good Pair ◽

Experimental Values ◽

Fluctuation Model ◽

Good Agreement

In this paper further considerations has been given to the fluctuation model of diffusion, and equations have been derived which express the self-diffusivity of liquid metals as a function of temperature and pressure. For liquid metals which are characterized by pair potentials which are relatively deep compared with k T, D is predicted to vary in a linear fashion with T at constant volume. At constant pressure, the apparent activation energy is predicted to be equial to R T+R(β/β)T2 where β is the isothermal compressibility and β' is its temperature derivative. Further, the variation in the logarithm of D with respect to pressure is predicted to be equal to [ (1/2.3)β] (∂β/∂P) T . A test of the equations for liquid mercury shows good correlation between theory and experiment. For liquid metals which are characterized by a shallow well in terms of the pair potential, no simple statements can be made concerning the nature of the temperature dependence, and simple approximations cannot be made. A test of the derived equations is made for liquid sodium which fits this case and for which good pair potential data exist, and good agreement is obtained at 373 °K. The temperature dependence of D as a function of T at constant volume is derived, but cannot be tested because of insufficient experimental data.The case of thermodiffusion is discussed, and it is shown that experimental values of the heat of transport are consistent with predictions of the theory.

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Relationship between Pair Potentials and Liquid Structure

Canadian Journal of Physics ◽

10.1139/p73-243 ◽

1973 ◽

Vol 51 (17) ◽

pp. 1831-1839 ◽

Cited By ~ 26

Author(s):

L. E. Ballentine ◽

J. C. Jones

Keyword(s):

Structure Factor ◽

Liquid Metals ◽

Pair Potential ◽

Liquid Structure ◽

Main Peak ◽

Repulsive Core ◽

Pair Potentials ◽

Eigenvector Analysis ◽

Hypernetted Chain ◽

Generalized Eigenvector

The Percus–Yevick and hypernetted chain theories are used to investigate the sensitivity of the pair potential [Formula: see text] to errors in the measured structure factor S(K) for several liquid metals and nonmetals. The linear relation between small errors, [Formula: see text], is studied by means of a generalized eigenvector analysis. Only those combinations of errors in S(K) which correspond to large eigenvalues lead to significant uncertainties in [Formula: see text]. The general form of the dominant eigenvectors was found to be the same for all liquids studied, except near the critical point. With this same exception, the following conclusions hold: Errors in S(K) for small K have by far the greatest effect on [Formula: see text]; the depth of the attractive portion of [Formula: see text] is most sensitive to errors in S(K); the repulsive core of [Formula: see text] is insensitive to errors in S(K); and the height of the main peak of S(K) has very little effect on [Formula: see text].

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Correction to the Wills-Harrison Approach: Influence on the First Minimum of the Effective Pair Interaction

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.371.373 ◽

2013 ◽

Vol 371 ◽

pp. 373-377 ◽

Cited By ~ 1

Author(s):

Nikolai Dubinin

Keyword(s):

Transition Metal ◽

Pair Potential ◽

Pair Interaction ◽

Simple Metal ◽

Pseudopotential Theory ◽

Pair Potentials ◽

Effective Pair Potential ◽

Effective Pair

An influence of the degree of account of the non-diagonal couplings between d electrons sited on different atoms in a transition metal on the main characteristics of the first minimums of the Wills-Harrison (WH) effective pair potentials in liquid Fe, Co and Ni are investigated. It is found that at full aforementioned account the WH potential is transformed to the simple-metal-pseudopotential-theory effective pair potential and that first-minimum positions of WH potentials abruptly shift to right side at predominance of the non-diagonal d-d-couplings in a metal.

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Theoretical study on structures and magnetic properties of NaxV (x=1-12) atomic clusters

Science and Technology Development Journal ◽

10.32508/stdj.v18i2.1183 ◽

2015 ◽

Vol 18 (2) ◽

pp. 177-186

Author(s):

Thanh Tho Bui ◽

Khung Moc Trang ◽

Hong Van Nguyen

Keyword(s):

Magnetic Properties ◽

Transition Metal ◽

Theoretical Study ◽

Structural Parameters ◽

Atomic Clusters ◽

Atomic Orbitals ◽

Metal Atoms ◽

Transition Metal Atoms ◽

Interesting Difference ◽

Theoretical Results

Superatoms, novel entities have been studied extensively in recent years, can be stabilized by mixing with transition metal atoms for forming atomic clusters. The aim of this contribution is to present some recent theoretical results on the application of quantum calculations for examining the structures and magnetic properties of the atomic clusters NaxV (x=1-12) made from the mixing of Nax superatoms with vanadium, a transition metal atom. Optimized structures of NaxV (x=1-12) are determined by using the TPSSTPSS/DGDZVP DFT calculations. Characteristics of optimized structures, as structural parameters, values of the magnetic moment on the atomic orbitals are determined. The obtained results point out that: (1) the Na8V cluster is the most stable in NaxV (x=1-12) atomic clusters and (2) the value of themagnetic moment of Na8V cluster is mainly influenced by the orbital magnetic momentof the atom V and this is an interesting difference from other remaining NaxV(x≠8) clusters

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Explanation of the Influence of Inflow Air Content on the Lift of Cavitating Hydrofoils

Journal of Fluids Engineering ◽

10.1115/1.4039252 ◽

2018 ◽

Vol 140 (8) ◽

Cited By ~ 1

Author(s):

Eduard Amromin

Keyword(s):

Experimental Data ◽

Theoretical Study ◽

Lift Coefficient ◽

Cavity Surface ◽

Air Bubbles ◽

Incoming Flow ◽

Fluid Density ◽

Air Content ◽

Theoretical Results ◽

Good Agreement

According to several known experiments, an increase of the incoming flow air content can increase the hydrofoil lift coefficient. The presented theoretical study shows that such increase is associated with the decrease of the fluid density at the cavity surface. This decrease is caused by entrainment of air bubbles to the cavity from the surrounding flow. The theoretical results based on such explanation are in a good agreement with the earlier published experimental data for NACA0015.

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