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The theoretical investigation of the superconducting state parameters (SSP) viz. electron-phonon coupling strength l , Coulomb pseudopotential m*, transition temperature TC , isotope effect exponent a and effective interaction strength NO V of Bec Zr1-c (c= 0.30, 0.35, 0.40 and 0.45) metallic glasses have been reported using Ashcroft's empty core (EMC) model potential for the first time. Five local field correction functions proposed by Hartree (H), Taylor (T), Ichimaru-Utsumi (IU), Farid et al. (F) and Sarkar et al. (S) are used in the present investigation to study the screening influence on the aforesaid properties. It is observed that the electron-phonon coupling strength l and the transition temperature TC are quite sensitive to the selection of the local field correction functions, whereas the Coulomb pseudopotential m*, isotope effect exponent a and effective interaction strength NO V show weak dependences on the local field correction functions. The TC obtained from H-local field correction function are found an excellent agreement with available theoretical or experimental data. Also, the present results are found in qualitative agreement with other such earlier reported data, which confirms the superconducting phase in the metallic glasses.

Superconducting state parameters (SSP) viz. electron-phonon coupling strength l, Coulomb pseudopotential m*, transition temperature TC, isotope effect exponent a and effective interaction strength NO V of seven Cu1-c Snc binary metallic glasses have been reported using Ashcroft's empty core (EMC) model potential for the first time. Five local field correction functions proposed by Hartree (H), Taylor (T), Ichimaru-Utsumi (IU), Farid et al. (F) and Sarkar et al. (S) are used in the present investigation to study the screening influence on the aforesaid properties. The TC obtained from H-local field correction function are found in qualitative agreement with available experimental data and show linear nature with the concentration c of element Sn. A linear TC equation is proposed by fitting the present outcomes for H-local field correction function, which is in conformity with other results for the experimental data. Also, the present results are found in qualitative agreement with other such earlier reported data, which confirms the superconducting phase in the metallic glasses.

The study of the electrical resistivity rL of alkali Na-based binary alloys Na1-xLix, Na1-xKx, Na1-xRbx and Na1-xCsx have been made by well-recognized model potential of Gajjar et al. The most recent exchange and correlation functions due to Farid et al (F) and Sarkar et al (S) are used for the first time in the study of electrical resistivity of liquid binary mixtures and found suitable for such study. The results, due to the inclusion of Sarkar et al's local field correction function, are found superior to those obtained due to Farid et al's local field correction function. Electrical resistivity of Na-based binary alloys compare well with the experimental data available in the literature.

The vibrational dynamics of Mg70Zn30 metallic glass has been studied at room temperature in terms of phonon eigen-frequencies of longitudinal and transverse modes employing three different approaches proposed by Hubbard-Beeby (HB), Takeno-Goda (TG) and Bhatia-Singh (BS). The well-recognized model potential is employed successfully to explain electron-ion interaction in the metallic glass; instead of using experimental values of the pair correlation function g(r), which is generated from the computed pair potential. The present findings of phonon dispersion curve are found in fair agreement with available theoretical as well as experimental data. The thermodynamic properties obtained by HB and TG approaches are found much lower than those obtained by BS approach. The pseudo-alloy-atom (PAA) model is applied for the first time instead of Vegard's Law.

The computations of the static and vibrational properties of four equiatomic Cs-based binary alloys viz. Cs0.5Li0.5, Cs0.5Na0.5, Cs0.5K0.5 and Cs0.5Rb0.5 to second order in local model potential is discussed in terms of real-space sum of Born von Karman central force constants. The local field correlation functions due to Hartree (H), Ichimaru-Utsumi (IU) and Sarkar et al. (S) are used to investigate influence of the screening effects on the aforesaid properties. Results for the lattice constants, i.e. С11, С12, С44, С12 – С44, С12 / С44, and bulk modulus B obtained using the H-local field correction function, have higher values in comparison with the results obtained for the same properties using IU and S local field correction functions. The results for the Shear modulus (C), deviation from Cauchy’s relation, Poisson’s ratio , Young modulus Y, propagation velocity of elastic waves, phonon dispersion curves and degree of anisotropy A are highly appreciable for the four equiatomic Cs-based binary alloys. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/27798

A well known pseudopotential is used to investigate the superconducting state parameters viz. electron-phonon coupling strength , Coulomb pseudopotential *, transition temperature ТС, isotope effect exponent  and effective interaction strength N0V for the AgxZn1 – x and AgxAl1 – x binary superconductors theoretically for the first time. We have incorporated here five different types of the local field correction functions to show the effect of exchange and correlation on the aforesaid properties. Very strong influence of the various exchange and correlation functions is concluded from the present study. The comparison with other such experimental values is encouraging, which confirms the applicability of the model potential in explaining the superconducting state parameters of binary mixture. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/27779

Well recognized empty core (EMC) pseudopotential of Ashcroft is used to investigate the superconducting state parameters viz; electron-phonon coupling strength λ, Coulomb pseudopotential μ*, transition temperature TC, isotope effect exponent α and effective interaction strength NOV of some (Ni33Zr67)1 – xVx (x = 0, 0.05, 0.1, 0.15) bulk amorphous alloys. We have incorporated five different types of local field correction functions, proposed by Hartree (H), Taylor (T), Ichimaru-Utsumi (IU), Farid et al. (F) and Sarkar et al. (S) to show the effect of exchange and correlation on the aforesaid properties. Very strong influence of the various exchange and correlation functions is concluded from the present study. The TC obtained from Sarkar et al. (S) local field correction function are found an excellent agreement with available theoretical data. Quadratic TC equation has been proposed, which provide successfully the TC values of bulk amorphous alloys under consideration. Also, the present results are found in qualitative agreement with other such earlier reported data, which confirms the superconducting phase in the s bulk amorphous alloys. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/30267

A well known empty core (EMC) model potential of Ashcroft is used to investigate the superconducting state parameters (SSP), viz. electron-phonon coupling strength λ, Coulomb pseudopotential µ ∗ , transition temperature TC , isotope effect exponent α and effective interaction strength N0 of (Ni33Zr67)1−xMx (M = Ti, V, Co, Cu) ternary amorphous superconductors. Five different types of local field correction functions, proposed by Hartree (H), Taylor (T), Ichimaru-Utsumi (IU), Farid et al. (F) and Sarkar et al. (S), are used in the present investigation to study the screening influence on the aforesaid properties. The TC values obtained from the Sarkar et al. (S) local field correction function are found in excellent agreement with available theoretical data. Quadratic TC equation has been proposed, which provides successfully the TC values of ternary amorphous alloys under consideration. Also, the present results are found to be in qualitative agreement with earlier reported data, which confirms the superconducting phase in the superconductors., Dobro poznat Ashcroftov model potencijala s praznom jezgrom (EMC) smo primijenili u istraživanju parametara supravodljivog stanja (SPP), i to jakosti vezanja elektron-fonon λ, Coulombovog pseudopotencijala µ ∗ , prijelazne temperature TC , eksponenta izotopnog učinka α i efektivne jakosti međudjelovanja N0 trojnih amorfnih supravodiča, (Ni33Zr67)1−xMx (M = Ti, V, Co, Cu). Primijenili smo pet različitih funkcija za popravku lokalnog polja, koje su predložili Hartree (H), Taylor (T), Ichimaru-Utsumi (IU), Farid i sur. (F) i Sarkar i sur. (S), radi proučavanja utjecaja zasjenjenja na ta svojstva. Dobivene vrijednosti s popravkom lokalnog polja prema Sarkaru i sur. su u odličnom skladu s poznatim teorijskim podacima. Predlaže se kvadratna jednadžba za TC koja uspješno daje TC vrijednosti za navedene trojne amorfne legure. Ishodi ovih računa su također u skladu s ranije objavljenim podacima, što potvrđuje supravodljivu fazu u tim supravodičima.

Theoretical computation of superconducting state parameters (SSP) viz. electron-phonon coupling strength l , Coulomb pseudopotential m* , transition temperature TC , isotope effect exponent a and effective interaction strength No V of face centered cubic Al1-C LiC binary alloys have been made extensively in the present work using a model potential formalism for the first time. A considerable influence of various exchange and correlation functions on l and m* is found from the present study. The present results of the SSP are found in qualitative agreement with the available experimental data wherever exist.

In the present article, the calculations of the lattice dynamical properties of four equiatomic binary alloys viz. Na0.5Li0.5, Na0.5K0.5, Na0.5Rb0.5 and Na0.5Cs0.5 to second order in local model potential is discussed in terms of real-space sum of Born von Karman central force constants. Well known Ashcroft’s empty core (EMC) model potential has been used to study the lattice dynamical properties. Instead of the average of the force constants of metallic Li, Na, K, Rb and Cs, the pseudo-alloyatom (PAA) is adopted to compute directly the force constants of four equiatomic sodium-based binary alloys. The exchange and correlation functions due to Hartree (H) and Ichimaru-Utsumi (IU) are used to investigate influence of screening effects. Results for the lattice constants i.e. C11, C12, C44, C12 − C44, C12/C44 and bulk modulus (B) obtained using the Hartree screening function have higher values in comparison with the results obtained for the same properties using IchimaruUtsumi (IU) screening function. The results for the shear modulus (C ′ ), deviation from Cauchy’s relation (C12/C44), Poisson’s ratio (σ), Young modulus (Y ), propagation velocity of elastic waves, phonon dispersion curves and degree of anisotropy (A) are encouraging for the four equiatomic Na-based binary alloys., Polazeći od Born von Karmanovih konstanti za središnju silu i zbrajanja u realnom prostoru, proveli smo račune za dinamička svojstva rešetke četiri binarne legure od sličnih atoma, Na0.5Li0.5, Na0.5K0.5, Na0.5Rb0.5 i Na0.5Cs0.5, do drugog reda u modelnom lokalnom potencijalu. Primijenili smo poznat Ashcroftov potencijal s praznom sredicom za račune dinamičkih svojstava rešetke. Umjesto prosjeka konstanti sila metalnih Li, Na, K, Rb i Cs, pretpostavili smo pseudo-atom legure (PAA) za izravno računanje konstanti sila četiri slično-atomne legure na bazi natrija. Uzeli smo Hartree-eve (H) i Ichimaru-Utsumi-eve (IU) funkcije izmjene i korelacija za istraživanje učinaka zasjenjenja. Ishodi za konstante rešetke, tj. C11, C12, C44, C12 − C44 i C12/C44, te volumnog modula (B) postignute s Hartree-evom funkcijom zasjenjenja veće su od ishoda tih veličina izračunatih Ichimaru-Utsumi-evom (IU) funkcijom zasjenjenja. Ishodi za modul smika (C ′ ), odstupanje od Cauchy-eve relacije (C12/C44), Poissonov omjer (σ), Youngov modul (Y ), brzine elastičnih valova, fononske disperzijske krivulje stupanj anizotropije (A) važni su podaci za ove četiri binarne legure sličnih atoma na bazi natrija.