Locality in electronic structure: an introduction to the recursion method

The electronic density of states (DOS) of both pure and Co-substituted YBa 2 Cu 3 O 7 has been calculated by a recursion method. The results show that the total DOS at the Fermi level of YBa 2 Cu 3 O 7 mainly comes from the contributions of the O 2p and Cu 3d orbitals. After Co doping, the O 2p–Cu 3d bonds are destroyed while the O 2p–Co 3d bonds are formed at lower energies, and the total DOS at the Fermi level decreases strikingly. In addition, our results reveal that the CuO chain has a one-dimensional feature.

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Augmented Space Recursion Method for the Study of Electronic States of Binary Alloys

Bangladesh Journal of Scientific and Industrial Research ◽

10.3329/bjsir.v44i3.4397 ◽

1970 ◽

Vol 44 (3) ◽

pp. 255-264

Author(s):

M Abdus Salam ◽

Kabir Ahmed ◽

BP Barua ◽

MSI Aziz

Keyword(s):

Electronic Structure ◽

Density Of States ◽

Tight Binding ◽

Electronic States ◽

Density Of State ◽

Recursion Method ◽

Disordered Alloys ◽

Lmto Method ◽

Augmented Space ◽

Space Formalism

We have studied here the electronic structure of pure random disordered alloys formed by Ni with Cu and Au at different ratios by using the linearized tight-binding muffin-tin Orbital (TB-LMTO) method. We also used the recursion technique together with augmented space formalism for increasing the efficiency and the accuracy to calculate the component projected density of states. From the density of state, we can understand the Fermi energy, magnetic moment and binding energy at different alloy compositions. The band structure can be calculated from here also. These studies are helpful for experimentalists and metallurgists in designing materials and alloys with specific properties. Key words: Electronic structure, Alloys, TB-LMTO, Density of states, Augmented space recursion DOI: 10.3329/bjsir.v44i3. Bangladesh J. Sci. Ind. Res. 44(3), 255-264, 2009

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Electronic Structure of the ∑3[111] Grain Boundary and Doping Effect in Ni

MRS Proceedings ◽

10.1557/proc-318-571 ◽

1993 ◽

Vol 318 ◽

Cited By ~ 2

Author(s):

Wang Chongyu ◽

Zhao Dongliang

Keyword(s):

Electronic Structure ◽

Grain Boundary ◽

Tight Binding ◽

Boundary Segregation ◽

Grain Boundary Segregation ◽

Nitrogen And Phosphorus ◽

Recursion Method ◽

Theoretical Results ◽

Boron Nitrogen ◽

Interatomic Energy

ABSTRACTBased on the tight-binding bond recursion method, the energetics parameters of ∑3[111] grain boundary in nickel are investigated. The theoretical results indicate that the boron enhances interatomic energy between the host atoms, and between impurity and nickel atoms. Calculations of the energy of the grain boundary segregation show that boron, nitrogen, and phosphorus have the tendency to segregate onto the grain boundary and segregation property of boron is stronger than that of nitrogen and phosphorus.

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Tight-binding calculations of electronic structure and resistivity of liquid and amorphous metals

MRS Proceedings ◽

10.1557/proc-491-105 ◽

1997 ◽

Vol 491 ◽

Author(s):

S. K. Bose

Keyword(s):

Electronic Structure ◽

Transition Metals ◽

Linear Combination ◽

Tight Binding ◽

Amorphous Metals ◽

Recursion Method ◽

Sources Of Error ◽

Pseudopotential Approach ◽

Structure Of Liquid

ABSTRACTWe discuss various aspects of calculating the electronic structure of liquid and amorphous metals using the recursion method and the tight-binding linear muffin-tin orbitals (TB-LMTO) basis. Resistivity calculations for such systems based on the Kubo-Greenwood formula and the TB-LMTO-recursion method are presented and compared with similar calculations based on the linear combination of atomic and atomic-like orbitals (LCAO) and the chemical pseudopotential approach. Results for amorphous Fe and Co and liquid Hg, Pd, and some 3d transition metals are presented. Sources of error in the calculation and ways to improve upon the present calculations are discussed.

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DEEP LEVELS DUE TO VACANCY PAIRS IN SILICON

International Journal of Modern Physics B ◽

10.1142/s0217979289000634 ◽

1989 ◽

Vol 03 (06) ◽

pp. 863-870 ◽

Cited By ~ 1

Author(s):

HONGQI XU ◽

U. LINDEFELT

Keyword(s):

Electronic Structure ◽

Band Gap ◽

State Energy ◽

Energy Levels ◽

Mean Value ◽

Deep Levels ◽

Nearest Neighbour ◽

Recursion Method ◽

The Mean ◽

The Many

The recursion method is used to investigate the electronic structure of undistorted vacancy pairs in silicon up to the seventh nearest-neighbour divacancy. The many energy levels associated with these vacancy pairs in and around the band gap region are calculated. The results of the calculation show that the strength of the interaction between a pair of vacancies depends as much on their relative positions as on the inter-vacancy distance, but the mean value of the gap-state energy levels remains essentially constant at the monovacancy level.

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