Electronic structure and stability of Ti-based [ital B]2 shape-memory compounds: X-ray and ultraviolet photoelectron spectra

Journal Article · Mon Nov 01 00:00:00 EST 1993 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.48.13296· OSTI ID:6035007

Shabalovskaya, S ^[1]; Narmonev, A ^[2]; Ivanova, O; Dementjev, A ^[3]

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1. Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011 (United States)
2. Central Research Institute of Black Metallurgy, Institute of Precise Alloys, Moscow (Russian Federation)
3. All Union Research Centre of Surface and Vacuum, Moscow (Russian Federation)

The evolution of x-ray photoelectron and ultraviolet spectra and their modification at the phase transformation [ital B]2-[ital B]19([ital B]19[prime]) of equiatomic Ti[ital M] and quasibinary Ti(Ni,[ital M]) compounds, where [ital M] stands for Fe, Co, Ni, Pd, Pt, Au, and Cu, are presented. Investigation of x-ray photoemission spectroscopy includes valence bands, satellites, and core-level energy studies. As the atomic number of [ital M] increases (both within the same period and along the group), its [ital d] states become more localized, the maximum and the center of gravity of the [ital d] bands shift towards the bottom of the valence band, and the [ital M] contribution to the density of states (DOS) at the Fermi level, [ital N]([ital E][sub [ital F]]), degrades. The DOS localization is accompanied by a spatial localization of the [ital M] [ital d] electrons resulting in weakening of the [ital d]-[ital d] covalent bonds between the alloy components and, thus, destabilizing the [ital B]2 phase. While the contribution of [ital M] [ital d] electrons to the DOS at [ital E][sub [ital F]] decreases, the Ti [ital d] electron portion increases to such an extent that, e.g., in TiPd and TiAu, the [ital M] contribution to [ital N]([ital E][sub [ital F]]) is almost negligible. The increase in core-level energy of all partners in compounds with respect to the elemental state is discussed in terms of covalency. The [ital M] [ital d] band localization leads to an increase of many-body interactions and, as a consequence, we managed to observe the Pd satellites without resonance enhancement. The [ital B]2-[ital B]19[prime] phase transition is accompanied by modification of the DOS which affects the Ti [ital d] states in general.

• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 6035007
• Journal Information: Physical Review, B: Condensed Matter; (United States), Vol. 48:18; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COBALT ALLOYS
ELECTRONIC STRUCTURE
COPPER ALLOYS
GOLD ALLOYS
IRON ALLOYS
NICKEL ALLOYS
PALLADIUM ALLOYS
PLATINUM ALLOYS
TITANIUM ALLOYS
CRYSTAL-PHASE TRANSFORMATIONS
PHOTOELECTRON SPECTROSCOPY
SHAPE MEMORY EFFECT
TEMPERATURE RANGE 0273-0400 K
TEMPERATURE RANGE 0400-1000 K
TERNARY ALLOY SYSTEMS
ALLOY SYSTEMS
ALLOYS
ELECTRON SPECTROSCOPY
PHASE TRANSFORMATIONS
PLATINUM METAL ALLOYS
SPECTROSCOPY
TEMPERATURE RANGE
360104* - Metals & Alloys- Physical Properties