Ionic interactions in platinum chloride linear-chain compounds

Journal Article · Wed Sep 01 00:00:00 EDT 1993 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.48.6065· OSTI ID:6261121

Batistic, I ^[1]; Huang, X Z; Bishop, A R; Saxena, A ^[2]

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1. Institute of Physics of the University, P.O. Box 304, 41001 Zagreb ( )
2. Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

Halogen-bridged transition-metal chain compounds have recently emerged as an important class of low-dimensional electronic materials with strong electron-lattice and electron-electron interactions. We introduce a many-body model for such materials which is quantitatively successful for highly valence-localized (strong charge-density-wave) members of the class, e.g., PtCl with various ligand structures. The model introduces nearest-neighbor Coulomb attraction [ital and] metal ion-ion electrostatic repulsion directly rather than through a linear Peierls-Hubbard Hamiltonian. These interactions have the effects of (i) modifying the on-site orbital energies, (ii) generating an effective [ital anharmonic] [ital intra]site electron-lattice coupling (leading to the formation of a charge-density wave even if the intersite electron-lattice coupling is weak), and (iii) acting as an effective [ital anharmonic] elastic force between neighboring metal and halogen atoms. The stoichiometric ground state and various defect states (polaron, bipolaron, kink, exciton) are studied within this framework by computing their optical absorption, Raman, and infrared spectra: The results agree well with available experimental data. Buckling of Cl atoms out of the chain axis in certain PtCl compounds is predicted to be important in order to obtain the observed Raman frequencies for [ital electron] polarons and bipolarons. Finally, a strong template'' effect is discussed by comparing two PtCl materials with different ligands and counterions.

• OSTI ID: 6261121
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 48:9; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360606* -- Other Materials-- Physical Properties-- (1992-)
ABSORPTION SPECTRA
CHLORIDES
CHLORINE COMPOUNDS
COULOMB FIELD
COUPLING
ELECTRIC FIELDS
ELECTRON-ELECTRON INTERACTIONS
ELECTRON-PHONON COUPLING
ELECTROSTATICS
EXCITONS
HALIDES
HALOGEN COMPOUNDS
INFRARED SPECTRA
INTERACTIONS
LEPTON-LEPTON INTERACTIONS
PARTICLE INTERACTIONS
PLATINUM CHLORIDES
PLATINUM COMPOUNDS
POLARONS
QUASI PARTICLES
RAMAN EFFECT
SPECTRA
TRANSITION ELEMENT COMPOUNDS