New layered ternary transition-metal tellurides

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1992

OSTI ID:7166763

Mar, A

Several new ternary transition-metal tellurides, a class of compounds hitherto largely unexplored, have been synthesized and characterized. These are layered materials whose structures have been determined by single-crystal X-ray diffraction methods. The successful preparation of the compound TaPtTe[sub 5] was crucial in developing an understanding of the MM[prime]Te[sub 5] (M = Nb, Ta; M[prime] = Ni, Pd, Pt) series of compounds, which adopt either of two possible closely-related layered structures. Interestingly, the compound TaPdTe[sub 5] remains unknown. Instead, the compound Ta[sub 4]Pd[sub 3]Te[sub 16] has been prepared. Its structure is closely related to that of the previously prepared compound Ta[sub 3]Pd[sub 3]Te[sub 14]. The physical properties of these compounds have been measured and correlated with the metal substitutions and interlayer separations. A new series of compounds, MM[prime]Te[sub 4] (M = Nb, Ta; M[prime] = Ru, Os, Rh, Ir), has been discovered. The structure of NbIrTe[sub 4] serves as a prototype: It is an ordered variant of the binary telluride WTe[sub 2]. Electronic band-structure calculations have been performed in order to rationalize the trends in metal-metal and tellurium-tellurium bonding observed in WTe[sub 2] and the MM[prime]Te[sub 4] phases. Extension of these studies to include main-group metals has resulted in the synthesis of the new layered ternary germanium tellurides TiGeTe[sub 6], ZrGeTe[sub 4], and HfGeTe[sub 4]. Because germanium can behave ambiguously in its role as a metalloid element, it serves as an anion by capping the metal-centered trigonal prisms and also as a cation in being coordinated in turn by other tellurium atoms in a trigonal pyramidal fashion. Structural relationships among these compounds are illustrated through the use of bicapped trigonal prisms and trigonal pyramids as the basic structural building blocks. The electrical and magnetic properties of these compounds have been measured.

• Research Organization: Northwestern Univ., Chicago, IL (United States)
• OSTI ID: 7166763
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602* -- Other Materials-- Structure & Phase Studies
360606 -- Other Materials-- Physical Properties-- (1992-)
CHALCOGENIDES
CHEMICAL PREPARATION
CRYSTAL STRUCTURE
HAFNIUM COMPOUNDS
HAFNIUM TELLURIDES
IRIDIUM COMPOUNDS
IRIDIUM TELLURIDES
NICKEL COMPOUNDS
NICKEL TELLURIDES
NIOBIUM COMPOUNDS
NIOBIUM TELLURIDES
OSMIUM COMPOUNDS
PALLADIUM COMPOUNDS
PALLADIUM TELLURIDES
PHYSICAL PROPERTIES
PLATINUM COMPOUNDS
PLATINUM TELLURIDES
REFRACTORY METAL COMPOUNDS
RHODIUM COMPOUNDS
RHODIUM TELLURIDES
RUTHENIUM COMPOUNDS
RUTHENIUM TELLURIDES
SYNTHESIS
TANTALUM COMPOUNDS
TANTALUM TELLURIDES
TELLURIDES
TELLURIUM COMPOUNDS
TITANIUM COMPOUNDS
TITANIUM TELLURIDES
TRANSITION ELEMENT COMPOUNDS
ZIRCONIUM COMPOUNDS
ZIRCONIUM TELLURIDES